MX2014011275A

MX2014011275A - Absorbent articles with decolorizing agents.

Info

Publication number: MX2014011275A
Application number: MX2014011275A
Authority: MX
Inventors: Doohong Kim; Sangwook Lee; Zhangjun; Ali Yahiaoui; Junmo Gil; Franz Aschenbrenner; Shruti Aryal; Priscilla Eng Choo Goh; Kenneth G Heckner
Original assignee: Kimberly Clark Co
Priority date: 2012-03-30
Filing date: 2013-03-28
Publication date: 2014-10-06
Also published as: MX339896B; AU2013237964A1; RU2014141986A; CN104244887A; CN104203183A; KR101676147B1; MX2014011273A; US9161869B2; WO2013149033A1; AU2013238037A1; BR112014024436A2; DE112013001837T5; KR20140140560A; AU2016204024B2; DE112013001832T5; US9283127B2; BR112014023793A2; KR20140140555A; RU2636559C2; BR112014023785A2

Abstract

A feminine hygiene absorbent personal care article includes a topsheet layer, a backsheet layer, at least one absorbent core layer positioned between the topsheet layer and the backsheet layer and decolorizing agents positioned on at least one decolorizing agent-containing layer, adjacent the article side edges, with the decolorizing agent-containing layer extending laterally beyond the lateral side edges of the absorbent core layer and being noncontinuous over at least a portion of the article in the article transverse direction.

Description

ABSORBENT ARTICLES WITH DECOLORANT AGENTS FIELD OF THE INVENTION The present invention is generally directed to absorbent articles for personal care. In particular, the present invention relates to absorbent articles for the personal care of feminine hygiene having portions that come into contact with the exudates of menstruation, and that the portions can be used to chemically alter or physically separate such exudates.

BACKGROUND OF THE INVENTION Absorbent articles for the personal care of feminine hygiene are frequently used to collect and retain body fluids, fluids or exudates that contain menstrual fluid or blood. In the context of such products, comfort, absorbency, and discretion are three main attributes of the products and areas of interest to the user. In particular, users are frequently interested in knowing that such products will absorb significant volumes of menstruation exudates with the aim of protecting their undergarments, outer garments, or sheets from stains, and that such products will help them avoid the consequent embarrassment caused by such spots. Users are also interested in using products that can not be seen or felt through their underwear.

Ref.:251123 Absorbent personal hygiene feminine hygiene articles, such as sanitary napkins, pads and day-to-day protectors, typically include at least one or more absorbent layers enclosed between a top-facing, liquid-permeable layer of body-facing, and a layer of lower waterproof canvas, oriented towards the garment. The edges of the upper canvas and lower canvas layers are often bonded together at their periphery to form a seal around the article, thus containing the absorbent layers and any exudate received in the article through the upper canvas. During use, such articles are typically located in the crotch portion of an undergarment for the absorption of body exudates, and are held in place by adhesive strips located on the interior surface of the articles (oriented toward the garment ). Some of these items also include wing-like structures for wrapping around the wearer's undergarments to further secure them to the wearer's underwear. Such wing-like structures (also known as fins or tabs) are often manufactured from lateral extensions of the upper canvas and lower canvas layers.

For many women, it is totally routine to periodically observe their feminine hygiene items during its use, in order to monitor the appearance and spread of a menstrual insult (in order to avoid leaks throughout the day). For some women, a concern or cause of emotional distress with conventional absorbent articles for the personal care of feminine hygiene is the increasing appearance of a menstrual insult in the article, and specifically, the spreading of the menstruation spot to the lateral edges of a product. Although many women often do not care to see a specific spot in the center of a pad, and consequently, change the pad afterwards, some women prefer not to see an extensive stain, other than the centralized stain of the insult. Conversely, some women prefer to see an expanding patch, as this provides an indication of their flow level that day, as well as evidence that the pad is picking up such exudates. Obviously, the leakage of fluids when using such articles, particularly around the lateral edges of articles, is universally a cause of emotional concern. Such leaks can occur in the narrowest dimension of the product along longitudinally directed side edges, or along the areas of the wings or tabs. Product leakage can lead not only to consumer embarrassment, but also to a general loss of confidence in the use of the items.

Therefore, several attempts have been made to incorporate chemical compounds or structures in the female sanitary pads to separate the stains, direct the stains, direct the stains, mask the stains or discolor the menstruation stains; to make more efficient use of an absorbent product as much as possible; and reduce or avoid leaks. Such structures include engraved walls or channels, specific printed areas, walls of polymer barriers or impervious to other liquids, and the like. However, such attempts have not been completely successful in eliminating or addressing the leak problem, or reducing consumer concerns related to the spots, if they were to occur.

In addition attempts have been made to chemically alter and separate the components of menstruation along the depth direction of a pad, and thereby reduce the mental impact of a possible spot, because menstruation must pass an absorbent layer to the lower part of a sanitary napkin. For example, U.S. Patent No. 3,124,135 Olson, describes the use of salts in the inner layers of a pad (salt layer sandwiched between the layers of the absorbent core and having the same side dimensions of the absorbent layers), in order to discolor menstruation to the precipitate the darker-colored hemoglobin of menstruation, as the fluid travels in the depth direction of the pad. Such discoloration allows almost clear menstrual fluids to flow to several portions of the lower absorbent layers and away from the precipitated hemoglobin. Such discoloration further allows nearly clear menstrual fluids to potentially flow through a lower absorbent layer to the bottom of a pad, thereby reducing the occurrence of a visible spot on the underside of a pad. Olson's reference highlights the rigidity produced in a pad, as a result of the inner layers containing salt, and offers a softening solution for the pad, by using polyethylene glycol (hereinafter PEG) as an additional element with the salt elements impregnated in the inner layers of a pad. However, even with such combinations of salts and PEG, the placement of this chemical agglomeration compound in, or immediately near, the absorbent layers, and having the same side dimensions as the absorbent layers (along the depth axis) , can lead to blockage of absorbency pathways in an article. As a result of the redirected fluid a possible leak can result. The reference of Olson does not address stains that result from leaks outside the pad on the top surface of the pad, either as a result of fluid flow or saturation of an underlying absorbent layer. Olson's reference also fails to address the concern of consumers who prefer to limit their vision of a spot on a pad when they see a pad from the surface of the top canvas layer. United States Patent Publication 2012/0165773 to Nakashita et al. Also describes the placement of chemical compounds within the core layer. An additional reference describing an alternative technique for filtering through the use of a "depth filter" is US 6,350,711 to Potts et al. Yet another reference describing the use of specific salts to remove colored substances from aqueous fluids is US Patent Publication 2012/0215192 to Corbellini et al. Despite these references, there is still a need to reduce leakage, and alter the fluid that causes staining off the top surface of a female sanitary pad, in order to lessen the mental impact of a menstrual insult (and the potential blemish due on the run) for pad users, without interfering with the operation of the absorbent layers of the product; there is also a need for such alteration of the fluid that produces the spots without affect the "feel" of the product that can be affected by the addition of salts; and there is further a need for a pad that limits the potential for stains as well as the consumer's view of a stain within the pad.

In addition, numerous absorbent structures have been developed to capture and retain bulky menstrual exudates released by women during their monthly cycles. With respect to this, the designs of such absorbent pads and daily pads have been refined over time, in order to make their use more comfortable (physically and emotionally) to consumers. For example, originally when they were first developed, the catamenial pads were thick and bulky structures, typically by the use of cellulosic wadding as their sole or primary absorbent layer, as described in U.S. Pat. 3,124,135 to Olson. Frequently such pads were easily visible through a user's outer garments, were used together with separate bands or tabs, and were uncomfortable to use for a user. These older pads with "tabs" or bands distributed the menstrual fluid predominantly in the depth direction of the pad, and predominantly leaked through the back (bottom) layer of the pad. This distribution of the fluids was driven by an adjustment close to the body, due to the use of the pad with a band construction. These pads were typically more than ¾ inch (1.9 cm) thick, and did not employ impermeable layers to prevent movement of menstrual fluid or air through the pad, and did not offer materials with a specific distribution to propel a lateral or longitudinal distribution of fluids. The oldest pads needed constructions that avoided the downward distribution of the red spot of the menstrual fluid. In addition, these pads did not contain any superabsorbent that could interfere with the distribution of menstrual fluid within the pad. As a result, such older constructions would not work adequately in modern pads attached to garments.

As the absorbent technology advanced, chemical compounds of superabsorbent polymers and layered substrates have been developed, allowing manufacturers to produce feminine absorbent products with progressively thinner configurations. As a result, sanitary napkins for feminine hygiene, pads and coatings have become significantly thinner and more absorbent, in order to offer both comfort and a certain discretion to a user. For the most part, such finer products have provided to users and surrounding third parties, with the impression that the user does not carry any form of protection against menstrual fluid in their underwear. Such articles have employed various garment attachment systems.

Modern garment-bound pads predominantly distribute menstrual fluid laterally and longitudinally, and, when leaks occur, predominantly leak away from the lateral edges (lateral portions, front and rear longitudinally directed) rather than through the lower part of the pad. This distribution of the leaks is driven in part by an adjustment of the pad not so close to the body, due to the attachment to the underwear or shorts, and to the construction of the pad. These pads are typically less than ¾ inch (0.63 cm) thick, have an impermeable layer to prevent movement of menstrual fluid and air through the pad, and use materials with a specific distribution to drive a lateral distribution and longitudinal. Modern pads also contain superabsorbent that can interfere with the distribution of menstrual fluid within the pad. The use of superabsorbent materials in core layers can lead to gel blockage that interferes with maximizing fluid absorption.

Even with these advances in absorbency, consumers continue to experience some leakage, typically from the fluid that spills from the surface of the upper canvas. Frequently, the spill is the result of several "structural" and "action-based" primordial causes, which cause dirt on the user's garments or bedding. For example, structural causes may include blocked absorbency pathways, or inability to handle fluid surges. The causes based on an action may be for example, consumers who experience leakage from an inappropriate placement of such products in their underwear, the use of these products by a consumer beyond the useful life designed for these products , the choice of consumers to use an absorbent article that is ill-equipped to handle their current menstrual flow regimen, or even, consumer movements during their daily activities that cause menstrual exudates to escape out of the absorbent article. Therefore, despite the development of many different absorbent technologies and structural designs, the leakage of the products and resulting stains caused from such leaks continues as a concern of potential users of such products. A mere adaptation of the oldest discoloration technology to pad structures modern would not be adequate, since it does not take into account the interference of modern superabsorbents (the superabsorbent competes with the fading technology for menstrual fluid), the lack of an adequate surface area, and the modern distribution of menstrual fluid in the pads, to avoid locally overwhelming the discoloration technology. Therefore there is a need for pad constructions that avoid the lateral and longitudinal distribution of the red spot of the menstrual fluid.

It is known to use certain sensors or condition change indicators with absorbent articles for feminine hygiene and other types of absorbent articles, to notify a user or caretaker of the imminent need to change such article as a result of a change in condition . Such devices can help provide consumers with emotional states of calm, knowing that the devices actively communicate the imminent failure of the product or the bodily states. Such indicators can be seen for example in the United States Patent Publications 2003/0130631 from Springer and 2007/0055210 from Kao. Although, such devices focus mainly on avoiding leaks or stains, or the appearance of some other condition, by limiting the time of use by the user, such devices do not help to alter the potential stain, because the leak really happens. Therefore there is an additional need for such products, which would reduce the emotional concerns of consumers regarding such spots, and the embarrassment that could accompany such spots if they occurred.

As previously described, certain chemical compounds are known for decolorizing blood stains in absorbent articles. For example, dye exchangers, neutralizers or bleaching compositions are described in the publications of the US patents 2008/0277621 of MacDonald, 2009/0061718 of Seidling, 2009/0062764 of MacDonald, WO2009133518 of Cunningham, U.S. Pat. num. 6,730,819 of Pesce, 7,105,715 of Carlucci, 3,124,135 of Olson, the publication of United States patent 2011/0004174 of Carlucci, and WO2011027295 of Corbellini, each of which is hereby incorporated by reference in its entirety. Such chemical compounds are often difficult to place uniformly on a surface of the product, or to manipulate in a sufficiently large surface area. Additionally, such chemical compounds can often result in a heavier, stiffer article, and subsequently a more uncomfortable feeling. Finally, such chemical compounds can cause alterations of menstrual fluid color that are less desirable for a consumer. Therefore, even with these chemical compounds available for discoloration, there is an additional need for absorbent structures that use both layered structures and chemical compounds, to reduce the severity / appearance of menstrual fluid stains on both a user's pad, as in a user's clothes or bedding. There is also a need for absorbent articles that reduce the consumer's concern about any stain that may occur, as well as items that use absorbent systems more effectively to take care of retained liquids.

SUMMARY OF THE INVENTION In one embodiment, a personal care absorbent article for feminine hygiene includes an upper canvas layer, a lower canvas layer, and at least one absorbent core layer located between the upper canvas layer and the lower canvas layer. The personal care absorbent article for feminine hygiene has a longitudinal axis and longitudinally directed lateral edges, a transverse axis, and a depth axis. The absorbent core layer includes side edges, longitudinally directed. A decolorizing agent is located in at least one layer containing bleaching agent within the personal care absorbent article for feminine hygiene, adjacent to the longitudinally directed side edges. from the article. The at least one layer containing decolorizing agent extends laterally beyond the lateral, lateral, longitudinally directed edges of the absorbent core layer. The at least one layer containing decolorizing agent includes a portion that is not continuous across the transverse axis of the personal care absorbent article for feminine hygiene. For example, in one embodiment, the at least one layer containing bleaching agent is a layer that includes two separate portions adjacent to the longitudinal side edges of the personal care absorbent article for feminine hygiene. In one embodiment, such two separate portions are separated by a portion of the article without any layer containing decolorizing agent. In another embodiment, such two separate portions are separated by a portion of the article without any decolorizing agent. In another embodiment, such two separate portions are attached to the upper canvas layer. In another embodiment, such two separate portions are attached to a layer underlying the upper canvas layer.

In another embodiment, a personal care absorbent article for feminine hygiene includes an upper canvas layer, a lower canvas layer, and at least one absorbent core layer located between the upper canvas layer and the lower canvas layer. The absorbent article of care Personnel for feminine hygiene has a longitudinal axis and lateral edges directed longitudinally, a transverse axis, and a depth axis. The absorbent core layer includes lateral, lateral, longitudinally directed edges. The bleaching agents are located in at least one layer containing decolorizing agent within the absorbent article for feminine hygiene, along the lateral edges of the article. The decolorizing agent-containing layer extends laterally beyond the lateral, lateral, longitudinally directed edges of the absorbent core layer, and desirably is separated into at least two distinct portions of the edges with an empty space or portion therebetween. , what leaves the center, the portion of the article receiving the insult, free of the layer containing decolorizing agent and / or decolorizing agent.

In an alternative embodiment of the personal care article, the article includes two separate portions of the layer containing decolorizing agent along the longitudinal side edges of the article. In a further alternative embodiment, the article includes two separate portions of the layer containing decolorizing agent along the longitudinally directed ends of the article. Still in a further alternative embodiment, the article includes four separate portions of the layer that contains decolorizing agent along each lateral edge of the article. In a further alternative embodiment of the personal care article, the bleaching agents are located on the upper canvas layer, either directly, or on a layer located on the upper canvas layer. Still in a further alternative embodiment of the article, a two layer top canvas layer includes a central material (center section) of longitudinally directed upper canvas and two upper canvas materials of longitudinally directed side edges, wherein a decolorizing agent is located on the two upper canvas materials of the lateral edges directed longitudinally. Still in a further alternative embodiment of the article, the two materials of the longitudinally directed side edges of an upper canvas include a laminate of a non-woven layer and a layer of a masking element.

Still in a further alternative embodiment of the article, the materials of the side edges of a top canvas layer include a laminate of a non-woven layer, such as a melt-blown layer, and a film layer. In yet another alternative embodiment of the article, the absorbent core layer includes core-edge side wraps, wherein a decolorizing agent located in the core-edge side wraps. Still in a further alternative embodiment of the article, the absorbent core layer includes a main absorbent layer and side edge materials bonded to the main absorbent layer that includes a decolorizing agent in the side edge materials. Such sidewall materials for example may be in a laminate or in a single layer adhered to the surface of the absorbent core facing the bottom canvas and projecting, as projections, laterally beyond the side edges of the core. In an alternative embodiment, such side edge materials may have a V-shaped or U-shaped cross-sectional configuration. Still in a further alternative embodiment of the article, the side edge materials are a laminate that includes an element. of masking. Still in a further alternative embodiment of the article, a main absorbent core layer is at least partially wrapped by a secondary absorbent layer. Still in a further alternative embodiment of the article, the total width in the transverse direction, between the most lateral edges of the layer containing the decolorizing agent (such as strips, layer or projections) is greater than the absorbent layer, or alternatively, greater than any layer that contains superabsorbent. That is, the width in the direction transverse between one side edge of the layer (s) containing decolorizing agent (such as between the separated outer side edges of the strips) desirably is greater than the width of the layer (s). (s) absorbent (s) or of the layer (s) containing superabsorbent (s).

In yet another alternative embodiment of the personal care absorbent article for feminine hygiene, the article includes a carrier layer of the decolorizing agent, located between the absorbent core layer and the lower linen layer. In a further alternative embodiment, the carrier layer is treated with a carbomer and a salt. Still in a further alternative embodiment, the core layer includes ammonium sulfate.

In yet another alternative embodiment of the personal care absorbent article for feminine hygiene, the bleaching agents are selected from PEG, PEO, MPEG, ammonium sulfate, carbomer and a mixture of zinc oxide. Still in a further alternative embodiment, the zinc oxide mixture includes zinc oxide, a binder, at least one surfactant and an acidifying agent. In yet another alternative embodiment of the personal care absorbent article for feminine hygiene, the bleaching agents include two different chemical compounds, each of the chemical compounds being present in a different layer in the article. In yet another alternative modality of the article Personal care absorbent for feminine hygiene, the decolorizing agent is a PEG, which desirably has an average molecular weight in the range of between about 1,000 and 400,000, alternatively between about 1,000 and 100,000, alternatively between about 1,000 and 35,000. In yet another alternative embodiment of the personal care absorbent article for feminine hygiene, the decolorizing agent is a PEG having an average molecular weight in the range of between about 4,000 and 12,000.

In a further alternative embodiment, a personal care absorbent article for feminine hygiene includes an upper canvas layer, a lower canvas layer, and at least one absorbent core layer located between the upper canvas layer and the lower canvas layer . The personal care absorbent article for feminine hygiene has a longitudinal axis and longitudinally directed lateral edges, a transverse axis, and a depth axis. The absorbent core layer includes lateral, lateral, longitudinally directed edges. A decolorizing agent is located in at least one layer containing bleaching agent within the personal care absorbent article for feminine hygiene, adjacent to the longitudinally directed side edges of the article. The at least one layer containing decolorizing agent extends laterally beyond the lateral, lateral, longitudinally directed edges of the absorbent core layer. The at least one layer containing decolorizing agent includes a portion that is not continuous across the transverse axis of the personal care absorbent article for feminine hygiene. The at least one layer containing decolorizing agent includes a laminate of a non-woven melt-blown layer and a film layer. In yet another alternative embodiment, the layer containing decolorizing agent is a strip of material treated or partially coated, which is treated or partially coated along a longitudinal edge of the strip. In one embodiment, such a strip is a strip of the meltblown layer of microfibers, or a strip of the meltblown layer of microfibers and film laminate.

In yet another alternative embodiment of the invention, such bleach-containing layers are located along the edges of an absorbent article (feminine sanitary pad). Still in a further alternative embodiment of the invention, such bleach-containing layers are located along the longitudinally directed side edges (most lateral edges) of a feminine sanitary pad. In yet another alternative embodiment of the invention, such layer or layers containing decolorizing agent are located along both the edges longitudinally directed laterals as of the edges of the longitudinal ends (front and rear ends) of the female sanitary pad. In another alternative embodiment of the invention, such a layer or layers containing decolorizing agent are located adjacent (within 2-5 cm) to the longitudinally directed side edges of the female sanitary pad. In another alternative embodiment, the placement of layers containing the decolorizing agent within a feminine sanitary pad results in a smaller size of the stain visually apparent on the surface of the upper canvas layer, as compared to the size of the layered stain. internally located, or the absorbent core layer (s). Such size of the stain on the upper canvas layer may be less along the transverse direction of the pad (or in lateral directions) or along the longitudinal directions of the pad, depending on the placement of the layers that They contain decolorizing agent. In yet another alternative embodiment of the invention, such a layer containing decolorizing agent is presented as two portions located in the same plane within a female sanitary pad, and is positioned symmetrically about the central longitudinal direction of the pad (or spindle). In another alternative embodiment of the invention, the bleaching agents in the layer that Contains decolorizing agent are soluble in the menstrual fluid.

The objects and advantages of the invention are explained below in the following description, or can be learned by carrying out the invention.

BRIEF DESCRIPTION OF THE FIGURES A complete and workable description of the present invention is more particularly set forth in the remainder of the description which includes reference to the appended figures in which: Figure 1A is a top perspective view of an embodiment of the present invention in the form of a feminine hygiene pad (also known as a personal care absorbent article for feminine hygiene); Figure IB is a fragmentary perspective exploded view of the female hygienic pad embodiment of Figure 1A of the present invention; Figure 1C is a cross-sectional view of a modality of the two-layer top canvas layer of the female sanitary pad embodiment of Figure 1A, taken along the lines 1C-1C; FIG. ID is a cross-sectional view of an alternative embodiment of the two-layer upper canvas layer of the female hygienic pad embodiment of Figure 1A, taken at approximately the same position as lines 1C-1C; Figure 1E is a cross-sectional view of an alternative embodiment of the two-layer upper canvas layer of the female hygienic pad embodiment of Figure 1A, taken at approximately the same position as the lines 1C-1C; Figure 1F is an enlarged partial cross-sectional view of a lateral material embodiment of the upper canvas layer in the embodiment of Figure ID with the core material layer of the upper canvas removed; Figure 1G is a partial top perspective view of the embodiment of Figure 1A with the upper canvas layer and the airlaid layer removed, showing the overlapping projections outside the core layer; Figure 1H is a partial cross-sectional view of the embodiment of the female hygienic pad of Figure 1G, taken approximately along the lines 1H-1H; Figure II is a top plan view of the Figure 1G; Figure 1J is a cross-sectional view of an alternative core, and projection structures for the female hygienic pad embodiment of Figure 1A, and is a replacement for the toothed core with wraps that they contain the superposed / projected discoloration agent (projecting from the sides of the core) that is specifically shown in Figure 1A; Figure 1K is a cross-sectional view of an additional alternative structure of the core layer for the female hygienic pad embodiment of Figure 1A with core projections, and is a replacement for the dentate core with overlapping shells containing the agent of discoloration (projections), which is specifically shown in Figure IB; Figure 1L is an exploded cross-sectional view of a further alternative embodiment of the layers of the female sanitary pad of Figure 1A in the area of the wings; Figure 1M is an exploded cross-sectional view of another alternative embodiment of the layers of the female sanitary pad of Figure 1A in the area of the wings; Figure 1N is an exploded cross-sectional view of additional alternative embodiments of the female sanitary pad of Figure 1A in the area of the wings; Figure 10 is a microscopy image of a coated top surface layer, containing decolorizing agent, in the form of a non-woven strip fused by coated blowing, according to the invention; Figure 1P is a microscopy image of an impregnated layer containing decolorizing agent, in the form of a non-woven strip melt blown treated, according to the invention; Figure 1Q is a top view in partial plan of the inner layers of an alternative embodiment of the female sanitary pad of Figure 1A, having wings of different shapes and layers containing decolorizing agent as characteristics of the wings; Figure IR is a fragmentary cross-sectional view of the female hygienic pad of Figure 1Q taken along the IR-IR line in the area of the wings; Figure 1S is a top plan view of the inner layers of an alternative embodiment of the female sanitary pad of Figure 1Q; Figure IT is an exploded cross-sectional view of the female hygienic pad of Figure 1S taken along the IT-IT line in the wing area; Figure 1U is an exploded cross-sectional view of an alternative embodiment of the female hygienic pad of Figure 1 in the area of the wings; Figure IV is an exploded cross-sectional view of an alternative embodiment of the pad feminine hygienic of Figure 1A in the wing area; Figure 1W is an exploded cross-sectional view of an alternative embodiment of the female sanitary pad of Figure 1A in the area of the wings; Figure IX is an exploded cross-sectional view of an alternative embodiment of the female sanitary pad of Figure 1A in the wing area, - Figure 1Y is an exploded cross-sectional view of an alternative embodiment of the pad feminine hygiene of Figure 1A; Figure 1Z is an exploded cross-sectional view of an alternative embodiment of the female sanitary pad of Figure 1A in the area of the wings; Figure 1AA is an exploded cross-sectional view of an alternative embodiment of the female sanitary pad of Figure 1A in the area of the wings; Figure 1AB is an exploded cross-sectional view of an alternative embodiment of the female sanitary pad of Figure 1 in the area of the wings; Figure 1AC is a top plan view of an alternative embodiment of an absorbent core layer of a female sanitary pad, with projections away from the longitudinal side edges; Figure 1AD is an exploded cross-sectional view of the alternate embodiment of the core layer of the Figure 1AC taken along line 1AD-1AD (along the transverse axis).

Figure 2A is a top plan view of an alternative embodiment of a female sanitary pad of the invention; Figure 2B is a cross-sectional view of Figure 2A taken along lines 2B-2B in the area of the wings; Figure 3A is a top view in stylized plan of a feminine hygienic pad of a previous material that includes typical dirt by a menstrual insult; Figure 3B is a stylized top plan view of a female sanitary pad of the invention illustrating dirt by a menstrual insult and targeted alteration of the stain, according to one embodiment of the invention.

DETAILED DESCRIPTION OF THE INVENTION DEFINITIONS As used herein, the term "non-woven fabric or weft" refers to a weft having a structure of individual fibers or yarns that are interlocked, but not in an identifiable manner as in a knitted fabric. Fabrics or non-woven wefts have been formed from many processes such as, for example, melt blow processes, bonding processes by spinning, thermoformed carded weft processes (also known as BCW and TABC), etc. The basis weight of the non-woven webs can generally vary, such as from about 5 grams per square meter ("grams per square meter") to 150 grams per square meter, in some embodiments from about 10 grams per square meter to about 125 grams. per square meter, and in some modalities, from approximately 25 grams per square meter to approximately 120 grams per square meter.

As used herein, the term "blown-fused web" generally refers to a web of non-woven fabric that is formed by a process wherein a molten thermoplastic material is extruded through a plurality of fine die capillaries, generally circular, in the form of fibers fused in convergent streams of gas (e.g., air) of high velocity which attenuate the fibers of molten thermoplastic material to reduce their diameter, which may be to a microfiber diameter. After that, the blown fibers are transported by the high velocity gas stream and are deposited on a collecting surface to form a web of randomly spread blown fibers. Such a process is described, for example, in U.S. Pat. 3,849,241 of Butin, et al., Which is hereby incorporated in its entirety as a reference for all purposes Generally speaking, the blown fibers can be microfibers that are substantially continuous or discontinuous, generally smaller than 10 microns in diameter, and generally sticky when deposited on a collecting surface.

As used herein, the term "spunbonded web" generally refers to a web containing substantially continuous fibers of small diameter. The fibers are formed by extruding a molten thermoplastic material from a plurality of fine, generally circular, capillaries of a spinner where the diameter of the extruded fibers is then rapidly reduced, such as, for example, by reducing stretch and / or other mechanisms Well known spunbond. The production of spunbonded webs is described and illustrated, for example, in U.S. Pat. 4,340,563 from Appel, and others, 3,692,618 from Dorschner, and others, 3,802,817 from Matsuki, and others, 3,338,992 from Kinney, 3,341,394 from Kinney, 3,502,763 from Hartman, 3,502,538 from Levy, 3,542,615 from Dobo, and others, and 5,382,400 from Pike, and others, which are incorporated herein in their entirety as a reference for all purposes. Spunbonded fibers are generally non-tacky when deposited on a collecting surface. Spunbonded fibers can sometimes have diameters of less than about 40 microns, and are frequently between about 5 to about 20 microns.

As used herein, the term "coform" generally refers to composite materials comprising a stabilized matrix or blend of thermoplastic fibers and a second non-thermoplastic material. As an example, the coform materials can be manufactured by a process wherein at least one head of the melt blow die is disposed near a gutter through which other materials are added to the web while it is being formed. The other materials may include, but are not limited to, fibrous organic materials such as wood pulp or non-woody such as cotton, rayon, recycled paper, pulp fluff and also superabsorbent particles, inorganic and / or organic absorbent materials, cut polymer fibers. treated etc. Some examples of these coform materials are described in U.S. Pat. 4,100,324 of Anderson, and others; 5,284,703 from Everhart, and others; and 5,350,624 to Georger, and others; each of which is incorporated herein in its entirety as a reference for all purposes.

As used herein, the terms "bleaching agent" or "bleaching agent" will be synonymous and refer to a chemical compound, or chemical mechanisms that discolor or aid in discoloration of blood spots, such as for example, when filtering or adding / agglutinating blood cells from fluids containing blood, lysing blood cells, causing alteration of the coloring agents of blood cells, or chemically altering in any other way the color perception of blood stains through color-modifying mechanisms, such as through oxidation or discoloration mechanisms, catalytic oxidation or enzymatic reaction, where the final effect is a decrease or elimination of the intensity of the red color in certain portions of an absorbent article for feminine hygiene and / or of the fluid flowing out of an article for feminine hygiene. Such a decolorizing agent effectively removes or alters the color of the fluid that potentially produces the spots, so that the fluid that unfortunately travels to the other side or over / through the absorbent article to the side edges of the article, has less color to stain garments or bedding, when a real leak of liquid occurs outside the article. By enclosing the coloring agents of the menstrual fluid in particular areas of the article outside the absorbent layers, the additional absorption of uncolored menstrual fluids (clear fluids of lower viscosity) can occur in all areas dedicated to the absorbent core. For the purposes of this description, the bleaching / decolorizing agents are located either in or on layers containing the decolorizing agent, which are located lateral to the central longitudinal axis of the absorbent article and, extending laterally beyond the longitudinally directed side edges of at least the main core layer (s) absorbent in the article. Such laterally extending bleaching agent-containing layers can project (as projections) beyond the lateral edge of the core (that is, it projects more laterally towards the longitudinal side edge of the article than the core layer (s)). ), which projects more laterally, either from a layer above the core (such as in the upper canvas layer) or below the core (when viewed along the depth axis), or from an attachment to the core itself. Such a layer or layers containing decolorizing agent are desirably located symmetrically about the longitudinal central axis (or direction) of the article (pad), and are located either together with, directly adjacent to, or adjacent to the side edges of the article (pad) , such as the side edges (the lateral edges directed longitudinally) or the edges of the ends of the article. In one embodiment, such layer (s) containing decolorizing agent are within 2 and 5 cm from the most lateral edge (longitudinally directed side edges) of the article. As used herein, the term "layer containing decolorizing agent" will refer to a material in a single layer, a multi-layer material structure, a laminate or sheet structure, or a combination thereof, which includes a decolorizing agent either in or on its structure of the material. The term "decolorizing agent-containing layer" can in one embodiment refer to two physically separated portions of the same layer that are within the same plane (especially when viewed along the depth axis) within an absorbent article, but which do not. they have no layer containing decolorizing agent or a decolorizing agent therebetween along the transverse axis of the article (direction). Such two physically separated portions may be two discrete, unconnected portions, such as separate strips of a material in the same plane, or alternatively two portions that are separated in a location in the same plane (such as along a portion). / region of the pad, located centrally, which receives the insult), but which are connected in some way along, or adjacent to, the peripheral edges of the pad. Examples of sheet structures are described in U.S. Pat. 6,932,929 and 6,896,669 to Woltman, each of which is hereby incorporated by reference in its entirety. The articles to be described include at least one layer containing decolorizing agent which desirably itself includes a portion that is not continuous through the transverse axis of the absorbent article, such as a personal care absorbent article for feminine hygiene.

As used herein, the term "masking element" will refer to the action of hindering, or to the actual physical structure that hampers, such as a canvas or layer of material, which hinders the visualization / perception of a blood stain. , as opposed to a chemical agent that alters the color of the fluid or the stain itself. Such a masking element is desirably a fibrous hydrophobic barrier film or material. Such a masking element, for the purposes of this invention, is desirably not absorbent, although it may be permeable to liquids. In one embodiment, it would be a non-absorbent and impervious to liquids, such as a polyolefin film.

As used herein, the terms "superabsorbent polymer", "superabsorbent" or "SAP" are used interchangeably and will mean polymers that can absorb and retain extremely large amounts of a liquid relative to its own mass. Water-absorbing polymers, which are classified as hydrogels, which can be cross-linked, absorb aqueous solutions through hydrogen bonds and other polar forces with the molecules of Water . The ability of an SAP to absorb water is based in part on the ionicity (a factor of the ionic concentration of the aqueous solution), and the functional polar groups of the SAP that have an affinity for water. SAPs are typically produced from the polymerization of acrylic acid mixed with sodium hydroxide in the presence of an initiator to form a sodium salt of polyacrylic acid (sometimes referred to as sodium polyacrylate). Other materials are also used to produce a superabsorbent polymer, such as polyacrylamide copolymer, ethylene-maleic anhydride copolymer, cross-linked carboxymethylcellulose, polyvinyl alcohol copolymers, cross-linked polyethylene oxide, and starch-grafted polyacrylonitrile copolymer. SAPs may be present in absorbent articles in the form of particles or in fibrous form, or as a coating on another material or fiber.

As used herein, the term "menstrual fluid simulator" refers to a simulated menstrual fluid that can be used to test personal care absorbent articles for feminine hygiene. This is described, for example, in U.S. Pat. 5,883,231 and in the publication of D, Guralski, Candee Krautkramer, Brian Lin, Jack Lindon, Teuta Elshani, Aneshia Ridenhour, entitled "A Biological Menses Simulant Using a" Baten "Homogenization Process", and published as Document IPCOM000198395D in ip.com, on August 6, 2010, each of which is incorporated as a reference in its entirety. For the purposes of this description, the menstrual fluid simulator described in these publications was used for the evaluation of the performance of the article.

Reference will now be made in detail to various embodiments of the invention, of which one or more examples are set forth below. Each example is provided by way of explanation of the invention and not of limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made to the present invention without departing from the spirit and scope of the invention. For example, features illustrated or described as part of one embodiment may be used in another embodiment to produce an additional embodiment. For the purposes of this application, similar characteristics will be represented by similar numbers between the figures. Although not expressly illustrated in each view or location, it should be understood that a traditional adhesive will be used for the construction of the absorbent article between each of the various layers of the article, for fixing the layers within the article.

In general terms, with the aim of addressing the concerns related to the stains perceived by consumers from potential leaks of the pads, to reduce the fear of embarrassment due to stains on clothes or bedding that result from such leakage, and to reduce the effort required in removing stains that can actually occur on clothes or in bedding , the invention provides a personal care absorbent article for feminine hygiene with targeted bleaching agents that can cause menstrual and menstrual fluid spots to turn a pale, colorless, or almost color, within selected portions of an article absorbent, before the fluid leaves the article. Such bleaching agents can cause such spots or menstrual fluid to turn light or pale yellow, for example, in order to reduce the potential risk of staining garments or bedding that may occur. With the reduction of the potential to produce stains, any leak that actually occurs will be easier to eliminate. Additionally, the invention provides a chemical bleaching compound used in combination with other structural barriers to prevent menstrual fluid from flowing out of the upper surface of the upper canvas layer, or to the side edges of the article and to reduce the visualization of the insult in the article, when viewed from the upper surface of the upper canvas layer. The invention provides regions with targeted chemical bleaching compounds, away from the core layer (s) and in some embodiments, separate regions of directed chemical bleaching compounds that are located within at least two distinct layers of an absorbent article, which do not prevent the direct absorption of menstrual fluid, once it has entered an absorbent layer, and whose layers are located away, or they are directed laterally away from the absorbent layer (s), and project laterally towards the lateral edges of the product, further away from the longitudinal central axis, than the lateral edges of the layer (s). s) core. Of the various layers of the article containing decolorizing agent, in one embodiment at least one such layer is desirably separated from the main structure of the absorbent layer.

More specifically, Figures 1A and IB, illustrate a perspective top view and an exploded perspective, respectively, of a first embodiment of an absorbent article of the present invention, in the form of a feminine sanitary pad. The pad has a longitudinal axis (which includes the longitudinal central axis L shown, as indicated by a dashed line), a transverse axis (and a transverse central axis T shown) and a depth axis D (or in the Z direction) ( as seen in Figure IB), which is the direction normal to the plane of the layers of the pad. The feminine hygienic pad (or personal care absorbent article for hygiene female) 10 has side wings 11 that extend out from the longitudinally directed side edges 90 of the article, contains a lower cloth layer 12, impervious to liquids, oriented toward the garment, and a liquid-permeable top layer, facing the user (for example, the upper canvas layer) 14. The lower canvas layer 12 and the upper canvas layer 14 interleaves at least one absorbent core layer 20. Although not expressly identified, it is shown that the upper canvas layer 14 includes optional engraving patterns in the form of waves / zigzags, circuit and arc patterns.

The lower canvas layer 12, which is generally impervious to liquids, is designed to face the internal surface, i.e., the crotch portion, underwear (not shown) or outer clothing of a wearer. Therefore the lower canvas includes a surface 12A oriented towards the core and a surface 12B oriented toward the underwear. The lower canvas layer 12 can optionally allow the passage of air or vapor out of the absorbent article 10, while still blocking the passage of the liquids.

Generally, any liquid impervious material can be used to form the lower canvas layer 12. For example, a suitable material that can be used is a microporous polymeric layer, such as a Polyolefin film made of polyethylene or polypropylene. In particular embodiments, a polyethylene film having a thickness in the range of about 0.2 mils (5.08 microns) to about 5.0 mils (127 microns), and particularly between about 0.5 to about 3.0 mils ( between 12.7 microns and 76.2 microns). A specific example of a material for the lower canvas layer is a polyethylene film such as that obtainable from Pliant Corporation, Schaumburg, 111., United States. Another example could include a polypropylene film loaded with calcium carbonate. In yet a further embodiment, the lower panel may be a hydrophobic nonwoven material with water barrier properties such as a nonwoven laminate, an example of which would be a four layer laminate, spunbond, meltblown, melting by blowing, spun bonding. Therefore the lower canvas layer 12 may be of a single or multiple layer construction, such as multiple layers of film or film laminates and fibrous non-woven layers. Even with a lower film layer of film, a non-woven fibrous layer may be used as the interior oriented surface for better "feel" or feel.

The upper canvas layer 14 can surround the layer (s) of absorbent core 20 so as to completely coat the absorbent core layer (s) and / or the lower canvas layer (coating not shown). Alternatively, the upper canvas layer 14 and the lower canvas layer 12 both can extend beyond the most lateral edges (41, 56, 100 for example) of the absorbent core layer (s) 20 and join between yes peripherally, either totally or partially, through the use of well-known fixation techniques. Typically, the upper canvas layer 14 and the lower canvas layer 12 are joined by adhesive bonding, ultrasonic bonding, or any other suitable joining method known in the art, the sealed edges defining a fully sealed peripheral edge of the pad. feminine hygiene 10. The feminine hygiene pad 10 can adopt various geometries, but will generally have opposite lateral sides (in the longitudinal direction of the product) and longitudinal ends.

The upper canvas layer 14 is generally designed to contact the wearer's body and is permeable to liquids. The liquid-permeable upper cloth layer 14 has one. surface 14A outward facing the user which can directly contact the body of the user and receive body exudates, and a surface 14B facing the absorbent core layer. The upper canvas layer 14 is desirably provided for achieving comfort and adaptability and functions to direct bodily exudates away from a user's body, through its structure and into the absorbent core layer (s) 20. The upper canvas layer 14 desirably retains little or nothing of liquid in its structure, so that it provides a relatively comfortable and non-irritating surface next to the tissues within the vestibule of a female carrier.

The upper canvas layer 14 can be constructed of any woven, non-woven or canvas material that is easily penetrated by the body exudates that come into contact with the surface of the lower canvas layer 12. Examples of suitable top canvas materials include the wefts of natural fibers (such as cotton), rayon, carded wefts of polyester, polypropylene, polyethylene, nylon, or other heat-bonded fibers, polyolefins, such as polypropylene and polyethylene copolymers, linear low density polyethylene , and aliphatic esters such as polylactic acid. In addition, finely perforated films and net materials can be used, as well as laminates of combinations of these materials. A specific example of a suitable top cloth material is a thermobonded carded web (BCW) made of polypropylene and polyethylene such as can be obtained from Sandler Corporation, Germany. The patents of United States no. 4,801,494 to Datta, et al. And U.S. Patent No. 4,908,026 to Sukiennik, and others teach various other upper canvas materials that can be used in the present invention, each of which is hereby incorporated herein in its entirety. The upper canvas layer 14 may further contain a plurality of openings (not shown) formed therethrough to allow the body fluid to pass more easily into the absorbent core layer (s) 20. The openings may be disposed at randomly or uniformly throughout the upper canvas layer 14, or may be located only in a narrow longitudinal band or strip disposed along the longitudinal axis L of the female hygienic pad 10, such as by the longitudinal central axis of the article. The size, shape, diameter and number of openings can be varied to suit the particular needs of an item.

As previously noted, the upper canvas layer 14 can also be engraved with any desired engraving pattern to define engraved channels. Etching techniques are well known to those skilled in the art. An engraving pattern not only creates an aesthetically pleasing surface, but channels can also facilitate the entry of menstrual fluid. Menstruation will tend to flow along the densified edges of the channels instead of of accumulating at contact points of the upper canvas layer 14.

The upper canvas layer itself may also be formed from one or more layers in a side-by-side arrangement along the longitudinal axis, as will be described in relation to Figures 1C, ID, 1E, 1L and 1M and others. Desirably, in one embodiment, the upper canvas layer has a basis weight of between about 15 grams per square meter and 100 grams per square meter.

In one embodiment, as seen in the cross-sectional view of the upper canvas layer 14 of Figure 1C, taken along lines IB-IB of Figure 1 (in the area of the wings), the layer of upper canvas 14, of two layers, is constructed of at least two different materials 15, 17 in a superposed arrangement, but substantially side by side along the longitudinal axis. Such a two-layer construction is generally described in U.S. Patent Nos. 5,961,505 of Coe, 5,415,640 of Kirby and 6,117,523 of Sugahara, each of which is incorporated herein by reference in its entirety. With specific reference to Figure IB, in one embodiment, a longitudinally directed central upper canvas material 15 is located along the longitudinal central axis L of the upper canvas layer 14. Such longitudinally directed central upper canvas material 15 is constructed desirably from heat-treated carded air-through-weave (TABC) materials with a basis weight of between about 15 and 100 grams per square meter. The above-described nonwoven, woven and film upper canvas materials can also be used as the longitudinally directed central upper canvas material 15 of the upper canvas layer 14. In one embodiment, such longitudinally directed central upper canvas material is constructed to Starting from TABCW with a basis weight of between approximately 20 and 50 grams per square meter, which is readily available from manufacturers of non-woven materials, such as Xiamen Yanjan Industry, Beijing DaYuan Nonwoven Fabrics and others. Different non-woven, woven or film canvas materials may be used since the upper canvas materials of the longitudinally directed side edges 17 (sometimes referred to as side coatings), are adjacent and joined to the longitudinally directed central upper canvas material 15. The selection of such materials from the upper canvas layer 14 will vary based on the desired overall attributes of the upper canvas. For example, it may be desired to have a hydrophilic material along the longitudinal central axis and materials of the hydrophobic barrier type along the longitudinal side edges of the article to prevent leakage, and to increase a feeling of dryness on those longitudinal side edges. Such longitudinally directed side edge materials 17 can be adhesively, thermally, ultrasonically or otherwise attached to the longitudinally directed central top material 15 along the longitudinally directed side edges 18 (on the oriented surface 14B towards the absorbent core layer) of the longitudinally directed central upper canvas material 15. In alternative embodiments, such longitudinally directed side edge materials can be attached to the surface of the upper canvas, facing the user, of the centrally directed upper canvas material longitudinally as seen in Figures 1L, 1M, and 1N. Such upper canvas materials of the longitudinally directed side edges 17 may be of a single layer or multilayer construction. In one embodiment, such upper canvas materials of the longitudinally directed side edges 17 themselves are adhesively bonded laminates, which include a chemical compound with decolorizing agent. In one embodiment, for example, such upper canvas materials of the longitudinally directed side edges 17, are constructed of a nonwoven top layer 17A, such as a melt blown microfiber material (MBMF, for its acronyms, as described further), intermediate layers of the decolorizing chemical agent 17B and the bonding adhesive 17D (as seen in Figure 1F), and a lower layer 17C of a hydrophobic barrier film. In such a configuration, the meltblown polypropylene microfiber upper material is desirably between about 10 and 100 grams per square meter in basis weight, with a fiber size of desirably between about 1 and 10 microns in diameter. Such material is available from Yuhan-Kimberly Ltd., Seoul, Korea. Because these meltblown materials are inherently hydrophobic, they are desirably treated with wetting agents for proper handling of aqueous fluids such as menstruation. Examples of such wetting agents include surfactants (or surfactants) with a hydrophilic-lipophilic balance (HLB) of at least 6, preferably between 7 and 18. The definitions of "surfactant" and "HLB scale" can be found in the textbook "Introduction to Colloid and Surface Chemistry", by Duncan J Sha, 4th edition, 1992, published by Butterworth-Heinemann. Ltd. A variety of surfactants can be used which includes those which are anionic, cationic or neutral from the point of view of the charge. In addition, mixtures of surfactants and other wetting agents can be used. The complement of the moisturizing agent Typical may be in the range between about 0.1 to 10% by weight, preferably between 0.2 to 5% by weight of the substrate. However, complement levels greater than 10% by weight can also be used. These wetting agents can have an effect of moving aqueous fluids through porous media such as a laminate of blown and / or multilayer microfibers, but further, it was found that only certain wetting agents can discolor fluids such as menstrual fluid. . However, the extent of discoloration depends on the type of wetting agent. The decolorizing agent in such a non-woven layer is desirably in one embodiment, a PEG, applied through slit coating in an amount of between about 10 and 30 grams per square meter. Such PEG is exemplified with PEG 8000 Carbowax Sentry. The two upper canvas materials of the longitudinally directed side edges 17 are shown as separate materials, with a central region on the upper canvas layer 14 therebetween, which is free of layers containing decolorizing agent (and agents).

The construction adhesive is desirably used to laminate the melt-blown microfiber layer in a complement of between about 1 and 5 grams per square meter and the film barrier layer is desirably a polyolefin film of a basis weight of between approximately 10 and 40 grams per square meter. In such laminated embodiments including both the decolorizing chemical and the adhesive, the decolorizing chemical and the adhesive can be employed in a single layer or in separate layers (as specifically seen in Figure 1F). The traditional adhesive for the construction of articles can be used to join the upper canvas materials of the longitudinally directed side edges 17 to the longitudinally directed central upper canvas material 15. Desirably, such chemical compound of the decolorizing agent is applied to the fused layer by blowing 17A by using a saturation technique such as an atomizer, foam, slot die or a contact roller. This desirably applies in an amount between about 3 and 60 grams per square meter. In such an embodiment, it is desirable that such a decolorizing chemical compound be applied either to the top of the blown fuse on the side facing the body or interspersed between layers. Such application of the bleaching agent may be across the entire surface of the meltblown layer (layer containing decolorizing agent), through a narrower width than the width of the meltblown layer, or alternatively, in a pattern of stripes along the length of the strip, with untreated areas between the stripes of the agent discoloration. If such scratch treatment is employed, such scratches can be used to create discolored regions between non-discolored regions in the strips, which serves as saturation warning indicators for the pad for consumers. In such a way, the discoloration of the fluid that potentially produces the stain is carried out by the article, as well as it provides a visual warning (through the appearance of colored and uncolored stripes) to the consumer of the impending saturation of the pad. . In an alternative embodiment, different concentrations of a bleaching agent may be applied on the stripes on a strip so that filtering occurs on a graduated scale across the transverse direction of the strip. Still in a further alternative embodiment, different decolorization agents can be used in different stripes on the strip, for similar reasons. When a film barrier layer 17C is used in the general design of the upper canvas, it may include opacifying agents, such as film pigments, which help the film to mask the spots along or adjacent to the side edges. of the pad 90. In this way the film layer would serve as a masking element on the pad to limit the visualization of a stain due to a menstrual insult along the central axis, longitudinal L of the pad, and towards the side edges of the pad. The film layer can further serve as a barrier layer to prevent rewetting of the surface of the upper canvas layer facing the wearer, as well as to prevent the flow of menstrual fluid to the side edges of an article. Such a film layer may in some embodiments include openings, such as to allow unidirectional transfer of fluid to an underlying core layer.

As seen in Figure ID, in an alternative embodiment, the upper canvas layer 14 may include topographic features 17E that extend out of the general plane of the upper canvas layer 14, and that result from side portions of the canvas layer which rise above the generally flat surface, either as a result of shrinkage elastic strands, or retractable threads 17F which are laminated to the upper canvas layer along the longitudinal axis L, and which are retracted after lamination or alternatively, during contact with menstrual fluid / moisture. Such strands or threads, although shown in two locations in the Figure, may be placed in several longitudinally directed (typically parallel) configurations, across the transverse axis of the article. Such a configuration is described, for example, in United States Patent Publication 2010/0152690 on Ong, which is incorporated herein by reference in its entirety.

Still in a further alternative embodiment of an upper canvas layer 14, as seen in the cross-sectional view of Figure 1E, instead of the longitudinally directed central upper canvas material 15 which is wrapped over the edges of the canvas materials of the longitudinally directed lateral edges 17 and attached thereto 19, (as seen in Figure ID), may instead be attached 19 adjacent the edge. In this manner, the upper canvas materials of the longitudinally directed side edges 17 could constitute the majority of the raised feature in the upper canvas layer 14.

The female hygiene pad 10 of Figures 1A and IB further contains at least one absorbent core layer 20 located between the upper canvas layer 14 and the lower canvas layer 12, which provides the ability to absorb and retain body exudates. The layer or layers of absorbent core 20 can be selected so as to demonstrate (n) a particular total absorbency capacity, depending on the type of article. For example, for feminine care products, the total absorbency capacity may typically be within the range of about 7-50 grams of menstrual fluid, and more typically may be within the range of approximately 30-40 g of menstrual fluid. Within the category of hygienic article for female care, it may be desirable to have different levels of absorbency depending on the type of product. For example, daily protectors for female care are typically used by consumers for "light" menstrual flow days, female care pads are typically worn by consumers for "regular" menstrual flow days, and pads Extra-large women's care is typically used by consumers for "overnight" or "heavy" menstrual flow days. For coatings for female care it may be desirable to have in one embodiment, an absorbency capacity of between about 1 and 5 grams of fluid. For female care pads it may be desirable in one embodiment to have an absorbency of between about 10 and 30 grams of fluid. For extra-large female care pads, in one embodiment it may be desirable to have an absorbency of between about 20 and 50 grams of fluid.

The absorbent core layer (s) 20 can generally be of a single layer structure or a combination of layered components, which desirably they demonstrate a certain level of compression ability, adaptability, are not irritating to the wearer's skin, and are capable of absorbing and retaining liquids and certain other body wastes. For example, the absorbent core layer (s) 20 may typically include an absorbent weft material of cellulosic fibers (e.g., wood pulp fibers), other natural fibers, synthetic fibers, woven or non-woven fabric canvases. , lightweight metal fabrics or other stabilizing structures, superabsorbent material, binding materials, surfactants, hydrophobic and hydrophilic selected materials, pigments, lotions, odor control agents or the like, as well as combinations thereof. In a particular embodiment, the absorbent web material is a cellulose fluff matrix, and may also include a superabsorbent material. The cellulose fluff material may comprise a mixture of fluff material of wood pulp. A desirable type of lint material is identified with the trade designation NB 416, available from the Weyerhaeuser Corporation, and is a highly absorbent, bleached wood pulp containing mainly softwood fibers. The absorbent materials can be formed into a weft structure by the use of various conventional methods and techniques. For example, the absorbent weft can be formed with a formation technique in dry, an air deposition technique, a wet forming technique, a foam forming technique (producing a foam or foam-like structure), or the like, as well as combinations thereof. A non-woven fabric coform material can also be used. The methods and apparatus for carrying out such techniques are well known in the art.

As illustrated in Figure IB, in one embodiment, the absorbent core layer 20 optionally includes front and rear protruding portions 21 longitudinally directed and portions serrated or cut in the core 22 along the longitudinal side edges 41 of the core. For the purposes of this invention, such toothed or cut portions 22 are not structurally necessary, but desirable for a compact core design. The core layer 20 may also optionally include an etching feature 23 for benefits in fluid handling, or for the stability of the layer when wet. In the illustrated embodiment, such etching feature 23 is not present along the central areas of the longitudinal and transverse axis of the absorbent core layer 20. Such etching characteristic may also be present in the center of the absorbent core layer if desired Such a core layer may be wrapped in fabric for its integrity.

In one embodiment of the core layer, the lateral, non-woven core-edge wraps 24 are initially located on the surface 12A facing the core of the lower canvas layer 12 to wrap around the longitudinally directed side edges. , of the absorbent core layer 20 and to contain a decolorizing agent whether or not the core layer includes cut or toothed portions 22. Such non-woven side core-edge wraps are desirably constructed from fused microfiber webs by blowing as previously described. A wide variety of materials of the core-edge side wrapping are contemplated, such as non-woven canvases, film linens or laminates thereof. In one embodiment, such material is wrapped around the side edges of an absorbent core layer 20 based on a cellulose fluff material in the finished product, and contains a decolorizing agent 40, (as seen in Figures IB and 1H) . It should be understood that in an alternative embodiment (not shown) the core-edge side wraps 24 may be wrapped around an edge of the non-toothed core layer as such. A side perspective view of the partial product can be seen in Figure 1G with the core-edge wraps 24, side, folded over the user facing surface of the core layer 20. A cross-sectional view of the The partial product of Figure 1G, taken along lines 1H-1H, can be seen in Figure 1G. As can be seen in Figure 1H, the nonwoven, core-edge wraps 24 contain a decolorizing agent 40 near the longitudinal side edges 41 of the absorbent core layer 20. Such placement of the bleaching agent does not interfere with the flow of exudates within the core layer in the central region, and discolor such exudates before such fluids can leave the longitudinal side edges of the core layer (in the narrowest dimension of the product). In Figure 1H a top plan view can be seen of a partial product, without an upper canvas and with a wrapped core, wrapped by core-edge side wraps 24, and with the core layer including toothed side edges 22, shown with broken lines. The two wraps are shown as separate strips of material projecting out of the core layer, with a central region therebetween which is free of layers containing the decolorizing agent (and agents). The wrapper 24, which in one embodiment is a polypropylene melt-blown microfiber material (MBMF), is desirably treated with the chemical bleaching agent 40, such as ammonium sulfate, in a supplement of between approximately 40 and 120 grams per square meter, alternatively between approximately 60 and 100 grams per square meter. In one embodiment, such wraps 24 are of a size between about 2 and 6 inches in length (5.08 and 5.5.2 cm) and between about 0.5 and 2 inches (1.27 and 5.08 cm) in width. In a further embodiment, such wraps have a basis weight of between about 10 and 100 grams per square meter, desirably between about 20 and 50 grams per square meter, more desirably about 30 grams per square meter.

In a further alternative embodiment, as illustrated in Figure 1J, a structure 25 of the main absorbent core layer may include a Z-folded structure along its longitudinally directed side edges. The structure includes bleaching agents 40 positioned along their longitudinally directed side edges, between layers 29A and 27A. As can be seen in Figure 1J, the structure 25 of the core layer generally includes features 26 of the Z-folded side edges. In this structure, it is desired that the absorbent core main layer 25 include a more top layer 27 which Orient to the top canvas layer in use (the top canvas layer is not shown). Such a core structure may be immediately adjacent to the upper canvas layer, or alternatively adjacent to an intermediate layer of transfer. Such uppermost layer 27 is desirably an air-laid structure of heat-stressed fibers yielding an average pore size between 1 and 500 microns, and having a basis weight of between about 40 and 200 grams per square meter. Such uppermost layer 27 partially envelops the lower absorbent layer 28 at the side edges. The shape of the core layer 25 in general from a top plan view (not shown) is desirably of a rectangular or dog bone shape, as is known in the art. The longitudinal side edges of the uppermost layer 27 are folded in order to partially wrap or overlap around a lower absorbent layer 28, which desirably is a canvas containing a superabsorbent polymer (SAP, for its acronym in English). Desirably, the canvas containing the superabsorbent polymer is a fluff-based material which is a combination of pulp and SAP enclosed with a tissue carrier and having a basis weight of between about 40 and 400 grams per square meter. Located at the side edges 29A and also immediately below 29B of the lower absorbent layer 28 (canvas containing the superabsorbent polymer), there is a layer of barrier film, desirably between about 10 and 40 grams per square meter, more desirably about 10. grams per square meter, and made from traditional film-forming polymers such as polyolefins, such as polyethylene. Such side film layers 29A are folded with the airlaid layer to create the Z-configuration observed in Figure 1J. The film layers are bonded to the sides of the airlaid layer and to the bottom surface of the lower absorbent layer 28. Such layers may further be attached to the lower canvas layer (not shown) or to any layer between the layer of lower canvas and the core layer. Desirably, the film layers are opaque and include opacifying pigments in sufficient amount (as is known in the subject matter of films) to hinder the viewing of any spots present below them in the underlying air-laid layer 27A. It should be recognized that the individual layers in this alternative layer of absorbent core 25 can be joined by the use of traditional joining techniques such as thermal, ultrasonic or adhesive processes, within the core layer structure 25 itself, then joined by use from any of these methods to the remaining structure of the absorbent article. Such an alternative structure of the core layer directs any insult to the layer with menstrual fluid that is not maintained within the lower absorbent layer 28, so that it flows along the structure in Z-folded projection. By flowing along of the Z-fold, the menstrual fluid spots are masked by the 29A film layers of the top view by the Z-shape (when viewed through the top canvas), and are bleached along the sides by the agents bleaching 40. It should be recognized that although not shown in this figure, a lower canvas layer 12 would similarly be located below (along the axis D) and adjacent to the film layer 29B and the airlaid layer 27A . It should be appreciated that any stain within the absorbent core layer 25 of this embodiment is masked from the view of the top canvas layer, which makes any insult appear centralized within the article, and has clean longitudinal side edges. Any leakage of a menstrual insult from the longitudinally directed side edges of such a core will also discolor before leaving the female sanitary pad. As an alternative to this embodiment, such film layers 29A and 29B can be replaced with a fibrous material, or a chemically treated fibrous material, designed to provide a hydrophobic barrier. Such an alternative structure 25 for the core layer can be used in conjunction with any of the above-described top canvases or in a further embodiment, with any type of traditional topcoat layer, such as with a homogeneous perforated film or nonwoven permeable layer. As with the above embodiments, the layers containing decolorizing agent are separated by an area for the central insult of the article without discoloration agent.

Still in a further alternative embodiment of an absorbent core layer structure for use in the female sanitary pad of Figure 1A, a cross-sectional view of an absorbent core layer construction is illustrated in Figure 1K. Although the top plan view of such a structure may be rectangular or dog bone shaped as previously described (and not shown), the cross-sectional view of the alternative embodiment includes a main absorbent layer 31, which is attached 34 of adhesive or in any other manner along the longitudinal side edges of its clothing-facing surface, to a non-woven layer laminate 33 and V-folded film 32 projecting away from the main absorbent layer 31 Such a V-folded laminate is essentially a projection directed laterally away from the core layer which is shown along both longitudinal side edges of the core layer, separated by a central region without discoloration agents. In such embodiment, the main absorbent core layer 31 may be of any traditionally used absorbent material, such as a core based on fluff, lying in the air, or compressed containing SAP. Desirably in such an embodiment, a layer of masking film 32 is located along the inner surface of the V-fold. Such a film layer can be of any of the traditional barrier film materials, but desirably in a It is made of polyethylene at approximately 10 grams per square meter. Alternatively, the basis weight of such a film layer is between about 10 and 40 grams per square meter. As with the masking film layers described previously, this film layer may include masking pigments to hinder vision of the stain when viewed from the upper canvas layer. Laminated to the film by any known method, desirably there is a layer containing decolorizing agent (treated nonwoven). In such an embodiment, the treated non-woven material is desirably a web laid to thermosetted latex air or a web of melt blown microfibers with a basis weight of between about 20 and 150 grams per square meter. In the structural configuration of the core, the masking and discoloration of the spots can be achieved by the core structure (as described further with respect to the immediately preceding embodiment) but in a less complex core design. The alternative structure of the core layer it can be used together with any of the above-described top canvases or in a further embodiment, with any type of traditional topcoat layer, such as with a homogeneous perforated film or a permeable non-woven layer. Although shown in a raised configuration for ease of visualization, the absorbent core layer 31 and the V-folded, lower side laminate 35 are actually desirably joined to a lower layer (such as the bottom canvas layer) in the practice of modality. For the purposes of this invention, V-folded laminates can also be described as U-folded.

In any of the alternative absorbent core layers described above (Figures 1J and 1K), such layers act to retard that the spreading of a menstrual insult reaches the side edges of the absorbent article. This delay can result in an increase in the actual absorbency of the absorbent core and at the same time, provide a masking along the side edges of the pad to address the consumer's emotional concerns about extensive periods of menstruation in the pad.

Still in a further alternative embodiment of the female sanitary pad of Figure 1A, as can be seen in Figure 1L, a cross-sectional view of several layers of the pad is shown. The pad it includes an upper canvas layer 14, and a lower canvas layer 12. Underlying the lower canvas layer 12 in the direction of the D-axis, adhesive patches 91 and 92 are found for attachment to the garments. The adhesive patch 91 for the garments is located along the longitudinal central axis of the pad of the garment-facing surface of the lower canvas layer 12, for direct attachment to the crotch portion of an undergarment. The two adhesive patches of the side wings 92 are located under the wings 11, also on the garment facing surface of the bottom canvas layer 12. The release / release sheets of the adhesive are respectively located on the patch. adhesive to the garment 91, and the adhesive patches of the wings 92. The upper canvas layer 14, includes a topographic / elevated 17E feature raised in part by retractable fibers 17F. The upper canvas layer 14 is wrapped around the longitudinally directed shrinkable fibers 17F and joined to the nonwoven upper canvas side layers 95 (upper canvas materials of the longitudinally directed side edges) through at least bonding points or tie lines 19. Desirably, the upper nonwoven lateral nonwoven layers are either a spunbond and film nonwoven laminate, a spunbond-melt tie layer laminate. blowing- melting by spinning-bonding by spinning, or alternatively, a non-woven hydrophobic material. Other types of materials have been previously described. A laminate 97 of a nonwoven st98 treated with a bleaching agent (a layer containing decolorizing agent and a bleaching agent) that is laminated to a masking element, such as an adhesive, is desirably positioned on top of the side layers. 99 film layer or other hydrophobic nonwoven layer, with the same dimensions. Such a laminate 97 is positioned along the longitudinal side edges of the pad in a configuration that places it adjacent the side edges 90 of the pad and over a portion of the wing 11. Desirably, such a nonwoven stlayer is an MBMF layer that is treated with a decolorizing agent, such as about 10 to about 30 grams per square meter of high molecular weight PEG, either by slot coating or spray application. Such a treated stis desirably between about 5 to 60 mm in width along the axis / transverse direction of the pad, and would extend laterally outward to cover both the longitudinal side edges 90 of the pad and a portion of the wings 11. Desirably such a MBMF layer is treated with a wetting agent and PEG. As shown, such layer containing decolorizing agent is shown separated in two portions, a portion along each side edge of the pad, with the layer containing no decolorizing agent (or agent) in the central region / portion of the pad (either in the central material of the upper canvas or in the core layer). It is desirable that such st extend over the entire length of the article, but a shorter stwould also work. Such shorter st in an alternative embodiment would extend between about 30 and 100 percent of the length of the article. Although it is more desirable to add such st along the longitudinal side edges of the article, in an alternative embodiment, they can be added in shorter lengths through the ends of the article in the transverse direction, to reduce the potential for leakage stains of the ends of the article. Still in an additional alternative mode, these can be added along all the edges of the article. Alternatively, instead of placing the strips above the materials of the upper canvas layer, such strips may be placed under the materials of the upper canvas layer, above the core layer (s) in the same general locations. The laminate of treated non-woven material and film 97 includes a film layer for masking purposes and positions the film layer oriented towards the non-woven side layers 95 of upper canvas (upper edge canvas materials). longitudinally directed laterals). In one embodiment, the masking film layer is a perforated film. In alternative embodiments, such a masking layer may be a hydrophobic and opaque nonwoven layer. As illustrated in Figure 1L, an absorbent layer 31 is located adjacent to an additional layer laid to the air 30. In one embodiment, the absorbent layer 31 is adhesively bonded 34 to a film laminate and treated nonwoven material (second layer containing bleaching agent), which has a film layer 32 located along the inside of a U-shaped or V-shaped configuration containing decolorizing agent arranged symmetrically along the longitudinal central axis of the article, and extending laterally outward from the side edges 100 of at least the absorbent core main layer 31, and desirably from all the absorbent core layers, if there is more than one. Such a U-shaped or V-shaped layer containing decolorizing agent is a projection directed laterally away from the core layer. Such projections may be located either outside of the garment-facing surface or of the surface facing the upper canvas of the core layer 31. The treated non-woven layer 33 is located in the illustrated embodiment, along the outside of the fabric. 35 U-shaped or V-shaped configuration. The non-woven layer can be one embodiment, either an airlaying layer or a MBMF layer as previously described and desirably treated with between about 20 and 200 grams per square meter of a decolorizing agent such as a salt. In one embodiment, the salt is desirably ammonium sulfate. The absorbent core layer 31 is desirably a lint layer, an airlayer layer or an SAP sheet. An airlayer layer 30 is desirably located between the upper canvas layer 14 and the absorbent core layer 31. Additionally, a bicomponent fluid distribution layer (BFDL) layer 96 is located between the air laying layer 30 and the upper canvas layer 14.

At least some of the materials containing decolorizing agent as contemplated in the embodiment, are made of longitudinal strips, which are located adjacent to, or along the longitudinal side edges of the absorbent article, and are separated by a portion of the article a along the transverse axis, not including the decolorizing agent or a portion of the layer containing decolorizing agent. The laminate of the layer containing decolorizing agent 97 are separate strips of material (two portions of the same layer) within the same plane of the article, but separated by a vacuum or area of the absorbent article (at least in the same plane) without the material of the layer that Contains decolorizing agent. In the embodiment, such a gap or area of separation between the strips coincides with the central region / portion of the insult of the absorbent article. In this way, the visible stain (in size) could be smaller on the surface of the upper canvas layer, than the size of the stain on an inner layer (or core layer), if there were no additional layers containing agent of discoloration in the central region of the insult in the underlying pad a, and closer to the longitudinal central axis of the pad than the laminates 97.

Still in a further alternative embodiment of the pad of Figure 1A, as can be seen in Figure 1L and showing a cross-sectional view, instead of having a separate laminate of a layer containing decolorizing agent / masking film layer bonded adjacent to the longitudinal side edges of the materials of the upper side canvas layer 95 (upper canvas materials of the longitudinally directed side edges, as in Figure 1K), the laminate itself of a layer of decolorizing agent / film layer of masking constitutes the lateral layers of upper canvas (as seen in Figures 1C, ID and 1E). Other structures are similar to those in Figure 1L. As can be seen in Figure 1M, the layer containing decolorizing agent in the upper canvas side layers 17A, 17C (upper canvas materials of longitudinally directed side edges), and U-shaped layers containing bleaching agent that extend laterally away from the lower surface of core 32, 33 (adjacent to lower canvas layer 12). ) each extends laterally towards the lateral edges of the article and towards the wings 11. Each pair is separated by a central portion without layers containing decolorizing agent (or agents). In particular, the materials of the upper canvas side edges extend toward the side edges and the wing areas at 110, and the U-shaped bleacher layers extend laterally away from the bottom surface of the core towards the side edge of the fabric. article and the wings, beyond the side edges of the core layer 111 located above them along the axis D. In this manner, for the embodiments illustrated in Figures 1L and 1M, there are two separate layers that they contain bleaching agent, each of which is part of laminates with masking layers (although no masking layers are required), each of which is not contained within the main absorbent layer of the article (so as not to impede the menstrual fluid flow within the main absorbent layers), and each of which extends beyond the side edges 100 of the core layer (s) of the article in the direction of the transverse axis.

Still in another alternative embodiment of Figure 1A, as shown in the cross-sectional view in Figure 1N, a feminine sanitary pad 200 is illustrated which includes a two-layer, top-facing, two-layer, top-facing layer 210 it has upper canvas materials of longitudinally directed side edges 212, and a central upper canvas material 214 longitudinally directed. The upper canvas layer could similarly be a single-layer upper-user-oriented canvas layer. In this alternative, an absorption layer 220, such as a heat-adhered air-pass carded weft layer (TABC) is placed underlying the upper canvas layer along the depth axis. Underlying the absorption layer along the depth axis, and extending laterally beyond the longitudinally directed side edges of both the absorption layer and core 250, 260 (towards the side edges of the pad) are two different structures to contain the chemical compound decolorizing agent. The two different structures are presented in the same modality illustrated for purposes of efficiency, but it should be understood that in the product of the actual pad contemplated, the same type of structure would be present along both lateral edges. longitudinally of the pad, desirably equidistant from the longitudinal central axis of the pad and extending laterally beyond the side edges of the absorbent core layer on each longitudinal side. Such separate structures would be separated by a portion of a layer without a layer containing decolorizing agent (or agent). Essentially, an empty space is present between two separate strips of the layer containing the decolorizing agent. As with the above embodiments, the separated strips are within the same plane of the absorbent article (along the axis D), but are separated by a space that coincides with the central portion of the insult of the absorbent article. Essentially, the layer containing the decolorizing agent is not continuous through the transverse direction of the article, in at least a portion of the layer containing the decolorizing agent, as shown in previous embodiments. In a first structure 230, a chemical decolorizing agent 232 with an application width (233) is placed either on top of, or within a layer containing decolorizing agent 23. Such a layer containing bleaching agent is desirably a meltblowing layer as previously described. Such a meltblown layer can itself adhere to a masking layer such as a film layer 236, the three layers are presented as a strip or series of directed strips longitudinally along the longitudinal axis of the pad. Desirably, the chemical decolorizing agent, such as a PEG material, is applied in an amount such that it has a total application width (233) less than the underlying layer containing the decolorizing agent 234, and is located throughout. of the most lateral upper edge (edge oriented towards the upper canvas) of the underlying layer 234. Alternatively, such a structure may be in a Z-folded configuration 240, which includes the chemical bleaching agent 242 on a folded surface oriented towards the top canvas. As with the above structure 230, a blow-melt layer 244 containing an agent, with a layer of masking film 246 is desirable to prevent exudates from the core layer (s) from flowing back. to the upper canvas layer, and in addition to mask the core spots when viewed through the upper canvas layer 210. In such embodiments, such chemical compound decolorizing agent is desirably applied through slit coating with a complement of light treatment with surfactant of less than about 5 percent, printing, or first mixing of such PEG in solution, with a surfactant treatment of less than about 5 percent and application by the use of traditional immersion and draining methods. Desirably the chemical compound of PEG is applied at an absolute concentration of the complement between approximately 1 and 40 grams per square meter, but desirably between approximately 5 and 30 grams per square meter. The molecular weight range of such added PEG is desirably between about 1000 and 200,000, more desirably between about 4000 and 15,000.

As can be seen in the microscopy images in Figures 10 and 1P showing such PEG applications, after the application of slot coating on a meltblown layer 234 containing the decolorizing agent, the chemical compound PEG decolorizing agent 232 is found mainly along the surface facing the top canvas layer of the meltblown layer, without significant penetration into the fibrous meltblown layer of the PEG / meltblown combination 235. After the alternative application through the use of the dip and drain methodology (which includes the PEG in solution), the PEG, 237 has penetrated the blow-melt fibrous web 234 of the general PEG / melt-blown combination 235.

In a her alternative embodiment, as seen in the partial plan top view of Figure 1Q and the cross-sectional, exploded, partial view of FIG. 1Q taken along the IR-IR line, the layers of an alternative embodiment of a female sanitary pad 300 include an upper canvas layer 305, an absorbent core layer 310, and a lower canvas layer 340. The pad includes wings 320, which in turn include a layered array 330 which contains the decolorizing agent. Layered arrangement 330 containing decolorizing agent extends laterally beyond the lateral edge 310 of the underlying core layer, when viewed along the depth axis. The layered arrangement 330 containing the decolorizing agent includes a decolorizing agent 332, such as a PEG applied to the surface facing the upper canvas layer of an underlying substrate 334, desirably a meltblowing layer. Optionally the combination of the agent and the substrate is laminated to a film backing or a paper canvas. The array 330 provides additional support to the wing structure 320 and may be positioned to overlap the core layer 310 as shown, or alternatively, may be included only along the wing and separated from the core layer (without overlapping) when observe along the depth axis (not shown). In such a case, the space between the array 330 and the core layer 310 can provide for easy wing folding, both in pad storage and during use, when wrapped around an edge of the underwear.

In a further alternative embodiment of a female sanitary pad similar to that shown in Figure 1Q, a top plan view and an exploded cross-sectional view of a female sanitary pad 400 are shown respectively in Figures 1S and 1S (taken along the IT-IT line in Figure 1S). The pad 400 includes an absorbent core layer 410 sandwiched between a translucent upper canvas layer 412 and a lower canvas layer 420. A substrate, such as a meltblowing layer or an airlaying layer 425 carries a decolorizing agent. 430 in selected portions, within the wing structures, beyond the most lateral edges of the core layer 410 (when viewed along the transverse and depth axis). In such a manner, the layer containing the decolorizing agent 425 provides additional support to the wings, and further provides a decolorizing functionality specifically in the areas of the wings 430.

Figures 1U to IX each provide alternative embodiments of structures of a female sanitary pad as shown in exploded cross-sectional views in the areas of the pad's wings. Each of the embodiments illustrates configurations of projections beyond the side edges of the respective absorbent core layers. As seen in the Figure 1U, a pad 500 includes a top canvas layer 510 and a bottom canvas layer 520. An absorbent core layer 530 is sandwiched between the upper canvas layer 510 and the lower canvas layer 520. The absorbent core layer 530 includes a partial wrapping of the core 534 in the form of a "C". Such a partial envelope of the core can be, for example, a polymer film. The core wrap 534 can span the entire length of the core layer 530 or more. An opening is defined, oriented towards the upper canvas layer 510. Around the core envelope 534 is located a layer containing decolorizing agent 532, which may be for example an airless or blown nonwoven layer. A chemical decolorizing agent 536, such as PEG, can be placed along the longitudinally directed, top-directed corners of the layer containing the decolorizing agent 532. The chemical decolorizing agent 536 is projected toward the side edges. of the pad, beyond the side edges of the core layer, without interfering with the flow of fluids in the core layer 530. There is a central portion of the article and the layers without the layer containing decolorizing agent (or the agent decolorizing). The layer (s) containing decolorizing agent includes (n) two separate portions along the longitudinally directed side edges of the (s) layer (s), and of the article.

As seen in Figure IV, a feminine sanitary pad 600 includes an upper canvas layer 602 and a lower canvas layer 604. An absorbent core layer 606 is sandwiched between the upper canvas layer 602 and the lower canvas layer 604 A layer containing decolorizing agent 608 is partially wrapped around the core layer, such as for example a blow-melt or air-laid structure. As with the above embodiment, such a layer 608 may extend over the entire length or more of the core layer 606. As with the above embodiment, the chemical bleaching agent 610 such as PEG, may be placed along the corners oriented toward the upper canvas, directed longitudinally, of the layer containing decolorizing agent 608, projecting towards the longitudinal side edges of the pad.

As seen in Figure 1W, a feminine sanitary pad 700 includes an upper canvas layer 702 and a lower canvas layer 704. An absorbent core layer 706 is sandwiched between the upper canvas layer 702 and the lower linen layer 704 The absorbent core layer 706 is partially wrapped with a perforated film core shell 708. The perforated film core shell 708, which is in the form of a "C" is itself covered with a layer containing the decolorizing agent 710, which can also be for example a non-woven layer of air-laid or blow-melt. The core sheath and the decolorizing agent-containing layer can extend the full length of the absorbent core layer 706. A chemical decolorizing agent 712 is projected from the longitudinally directed, upper-facing corners of the layer. containing the decolorizing agent 710.

As seen in Figure IX, a female sanitary pad 800, includes an upper canvas layer 802 and a lower canvas layer 804. An absorbent core layer 806 is sandwiched between the upper canvas layer 802 and the lower canvas layer 804. The side film layers 810, for the purpose of aiding the prevention of side leakage, are partially wrapped ar the absorbent core layer 806 along its length. A layer containing decolorizing agent 808 is partially wrapped ar the core layer 806 and the side film layers 810, and includes projections of the decolorizing agent chemical 812 along the longitudinal corners, facing the upper canvas.

As seen in Figure 1Y, which illustrates a view in cross-section, in exploded view of yet another alternative embodiment of the female sanitary pad of Figure 1A, a feminine sanitary pad 900 includes an upper canvas layer 902 and a lower canvas layer 904, which together sandwich an absorbent core layer multilayer 906 and 908. A layer 910 containing the decolorizing agent in the form of a matrix, contains or encapsulates the decolorizing agent, such as PEG. Such a matrix can be, for example, a foam or foam adhesive, with the decolorizing agent contained therein. Such a matrix projects toward the longitudinal side edges of the pad, more laterally beyond the longitudinal side edges of the core layers 906 and 908, when viewed along the depth and transverse axis.

As seen in Figure 1Z, which illustrates an exploded, cross-sectional view of another alternative embodiment of the female sanitary pad of Figure 1A, a female sanitary pad 911 includes a two-layer top sheet having upper canvas materials of the lateral edge 912 directed longitudinally and a central upper canvas material 916 directed longitudinally. Underlying the upper canvas materials of side edge 912 longitudinally directed and affixed thereto are layers 914 containing the decolorizing agent. The upper edge canvas materials Laterally directed laterals 912 are desirably made of hydrophobic materials, such as hydrophobic non-woven materials. The layers 914 containing decolorizing agent can also be of a hydrophobic material and include a coating of a decolorizing agent 918, desirably PEG, on the surface facing the absorbent core, with the absorbent core layer 950 underlyingly located throughout. of the depth axis, to the upper canvas core material 916 longitudinally directed and sandwiched between the longitudinally directed upper canvas core material 916 and the lower linen layer 952. In such an embodiment, each of the decolorizing agent containing layers 914 is desirably a meltblown layer, and are located between the longitudinally oriented upper edge material of the sidewall 912 and the uppermost material of the upperwall 916 longitudinally directed, but beyond the side edges of the core layer 950, when viewed along the axis of depth and the transversal. A line of adhesive 920 joins the edges of the layer containing the decolorizing agent with the edges of the longitudinally directed upper canvas core material 916.

As seen in Figure 1AA, which illustrates another exploded cross-sectional view of an alternative embodiment of the female hygienic pad of the Figure 1A, a female sanitary pad 930 includes a two-layer upper canvas layer having upper canvas materials of the longitudinally directed side edges 912 and a longitudinally directed upper canvas core material 916. Underlying the upper canvas materials of the longitudinally directed side edges 912 are the bleaching agents 918. The absorbent core layer 950 is located underlying the depth axis, the longitudinally directed upper canvas core material 916 and sandwiched between the central longitudinally directed upper canvas material 916 and the lower canvas layer 952. In such an embodiment, the decolorizing agent desirably lies between the upper canvas materials of the longitudinally directed side edges 912 and the central upper canvas material directed longitudinally 916, but beyond the lateral edges of the core layer 950, when viewed along the depth and transverse axis. A line of adhesive 920 joins the upper canvas materials of the lateral edges 912 longitudinally directed with the edges of the longitudinally directed upper canvas core material 916.

As seen in Figure 1AB, which illustrates another exploded cross-sectional view of an alternative embodiment of the female hygienic pad of the Figure 1A, a female sanitary pad 940 includes a two-layer top canvas layer including top sheet materials of the longitudinally directed side edges 912 and a longitudinally directed upper canvas core material 922. Underlying the longitudinally directed upper cloth core material 922 are the bleaching agents 918. The longitudinally directed upper cloth core material 922 is in the form of a "C" wrapped structure which is first treated on the longitudinal sides with the decolorizing agent 918 and then it is wrapped around such bleaching agents. The absorbent core layer 950 is located underlying the depth axis, to the upper canvas central material 922 longitudinally directed and sandwiched between the longitudinally directed upper canvas core material 922 and the lower canvas layer 952. In such an embodiment, the decolorizing agent is located beyond the side edges of the core layer 950, when viewed along the depth and transverse axis. A line of adhesive 920 joins the upper canvas materials of the longitudinally directed side edges 912 with the longitudinal edges of the longitudinally directed upper canvas core material 922.

As seen in Figures 1AC and 1AD, which illustrate an alternative embodiment of a 960 layer system absorbent core of a female sanitary pad of the invention, system 960 of the core layer, includes corner projections 962 outside the longitudinally directed side edges of core layer 964. Core layer 964 may be a layer which forms the pad or a canvas containing SAP, as is known in the art. The corner projections 962 are layers containing the decolorizing agent such as meltblown or airlaid materials, which are coated or otherwise treated with a decolorizing agent such as PEG. Desirably corner projections 962 are hydrophilic in nature.

As can be seen from the various embodiments described above, the decolorizing agent layers of the various embodiments extend laterally beyond the longitudinal side edges of the main absorbent core layers, such as 20, 28, 31 (laterally beyond of the longitudinal side edges of the core when viewed along the depth axis (D)). In many embodiments, the layers containing the bleaching agent further include masking layers laminated thereto to provide the pads with a potential for discoloration of the leaks (in two vital areas of the pad), as well as a masking of the spots. .

As noted from the various embodiments, the feminine hygiene pad 10 may additionally contain additional layers. For example, in one embodiment, the female sanitary pad 10 may contain a liquid permeable inlet layer located between the upper canvas layer 14 and the absorbent core layer 20. As seen in Figure IB and other subsequent figures , the female sanitary pad 10 includes an additional air-laying absorbent layer 30. Such an entry layer can be made of a material that is capable of rapidly transferring, in the D direction, the body fluid that is delivered to the upper canvas layer 14. The entry layer can generally have any desired shape and / or size. In one embodiment, the entry layer has a rectangular shape, with a length equal to or less than the total length of the female sanitary pad 10, and a width less than the width of the female sanitary pad 10. For example, a length of between about 150 mm to about 300 mm and a width of between about 10 mm to about 60 mm. Any variety of different materials has the ability to be used in the preparation of the input layer to perform the aforementioned functions. The material of the input layer can be synthetic, cellulose, or a combination of synthetic and cellulose materials. By For example, air-laid cellulosic fabrics may be suitable for the entry layer. The cellulosic fabric stretched to the air can have a basis weight ranging from about 10 grams per square meter to about 300 grams per square meter, and in some embodiments, between about 100 grams per square meter and about 250 grams per square meter. In one embodiment, the cellulosic fabric laid to the air has a basis weight of approximately 200 g / m2. The fabric stretched to the air can be formed from fibers hardwood and / or softwood. A fabric stretched to the air has a fine pore structure and provides an excellent capacity of absorption by capillarity, especially for the menstrual fluid.

Additional layers between the upper canvas layer and the absorbent core layer include transfer delay layers, permeable to liquids or absorption layers as are commonly known. Yet another layer that may be present between the upper canvas layer and the absorbent core layer includes a BFDL, which increases the absorbency by providing a large void space and may be manufactured from a TABCW, with a basis weight in a mode of between approximately 25 and 100 grams per square meter. Although side wings 11 are shown as being formed from extensions of the lower canvas layer 12 and the upper canvas layer 14 such that they are integral portions of pad 10, may also be non-integral structures, joined later. As an additional feature, but optional to the embodiments described, lines of polymeric material may be applied along the edges of, or adjacent to, the edges of any of the layers described (not shown). The polymeric material can be applied to the user-facing surface or the garment-facing surface of the layers, in order to create an additional hydrophobic barrier to stop or retard the flow of a diffuse menstruation spot.

Still in a further alternative embodiment of a female sanitary pad of the invention, as seen in the top plan view of Figure 2A and the corresponding cross-sectional view in Figure 2B taken along line 2B-2B of Figure 2A, targeted bleaching agents can be applied to multiple discrete and separate layers of an absorbent core structure. As seen in Figure 2B, for example, the female sanitary pad 120 includes a lower canvas layer 12 and an upper canvas layer 14. In one embodiment, a BFDL layer 65 is located adjacent to the upper canvas layer 14. Adjacent to the BFDL layer 65 is a multi-functional air-laying layer 60. Adjacent to the multifunctional air-laying layer 60 is a traditional fluff-based core layer 55. In one embodiment, the fluff-based core layer 55 can be treated throughout its structure with a decolorizing agent, or alternatively, treated with such an agent along the longitudinal side edges 56 only. Adjacent to the traditional fluff-based core layer 55 is a carrier layer 50 treated with a bleaching agent. The carrier layer may be manufactured from a variety of known materials, such as for example, a non-woven layer or a foam layer that has been treated either throughout its structure, or along the longitudinal side edges 53 with an adhesive agent. discoloration. In one embodiment, the carrier layer has a basis weight of between about 50 and 200 grams per square meter. In a further embodiment, the length and width dimensions of the BFDL layer are the same as the carrier layer. Still in a further embodiment, the bleaching agent is treated on the carrier layer 50, only at locations 52 on the carrier layer that are outside the peripheral dimensions of the fluff-based core layer 55 that is located above it. along the axis D. In this way, insofar as a menstrual insult travels through an absorbent core structure to its peripheral edges, it fades on or beyond its peripheral edges either through the outer edges of the core or by the carrier layer, so that any leakage of the pad to along the longitudinally directed side edges would be devoid of significant color or would be almost colorless.

It should be recognized that in yet another alternative embodiment of the invention, the structures described in Figures 2A and 2B can be further used in conjunction with the configurations of the upper canvas layer described in the previous figures.

Thus, in one embodiment the decolorizing agents are desirably separated into two or more distinct layers containing bleaching agent within the product, and if desired, may be employed in conjunction with masking elements and optionally barrier polymeric materials. Such decolorizing agent-containing layers are located laterally from the core layers and / or the initial regions of fluid deposition (along the longitudinal central axis of the article), so as to not obstruct the absorbency pathways within the Article. A central portion of the article and the layers are desirably free of the decolorizing agent (and the layer containing decolorizing agent). It should further be recognized that multiple types of bleaching agents can be employed in a single absorbent article. Still in a further alternative embodiment of the article, the total width in the transverse direction, between the most lateral edges of the layer containing decolorizing agent (such as strips, layer or projections) is greater than the absorbent layer (s), or alternatively, greater than any layer (s) containing superabsorbent. That is, the width in the transverse direction between one side edge to the other of the layer (s) containing (n) the decolorizing agent (such as between the outer side edge of separate strips, projections or carrier layer), it is desirably greater than the width of the absorbent layer (s) and of the layer (s) containing superabsorbent (s).

By employing the structural embodiments described herein, a discoloration region is created at or near the lateral periphery of the pad that is treated with the decolorizing agent. In this way, the bleaching agent helps to discard the color of the exudates that potentially produce spots at the edges of the product, and desirably outside the upper canvas layer, where leakage is more likely to occur in modern feminine hygiene absorbent articles. . The interior regions of the product may be substantially left untreated with the bleaching agents, thus, allowing the bleaching agents to be directed to the menstrual fluid in specific peripheral structures. This allows a user to observe and inspect the body exudates in the center of the product, and also allows the bleaching agents to apply only to those portions of the product needed to achieve the desired effect so that untreated regions / portions can continue to perform their functions, such as absorption or absorption by fluid capillarity, etc. without undue rigidity or without sacrifice of comfort. In addition, the use of bleaching agents directed to certain regions / portions of the article together with masking structures (if desired) provides additional emotional comfort for users who prefer not to see the spreading of menstrual insult spots, and also seek comfort Knowing that leaks that could result from the pad will result in a visibly less visible stain on a garment or bedding.

As can be seen in Figure 3A, which illustrates the progression of a stain by a menstrual insult in certain traditional feminine sanitary pads, the stain 72 due to menstruation can move in the absorbent layer towards the wings 11 of a pad 70. Custom-made that the stain spreads, retains its red color towards the wings 11, as seen in the wings 74. In comparison, an insult stain of a pad of the invention 80 as seen in Figure 3B, demonstrates a certain initial stain color in the central absorbent region / portion 82. As the structure of the pad changes toward the peripheral portions / regions the spot 84 due to the insult and the menstrual flow in dispersion undergoes a real and perceived color change from the initial spot 82, to the extent that the menstrual exudates progress towards the longitudinal lateral edges of the pad and the wings 11.

Desirable bleaching agents to be used in conjunction with the structural embodiments described herein include a broad array of chemical compounds. Although known bleaching agents may be used, it is desirable that bleaching agents be selected from the following categories of chemical compounds, for the following reasons.

In one embodiment of the invention, the decolorizing agent is desirably a menstruation filtration chemical compound, i.e., an agent that can precipitate, coagulate, separate the components per phase, or demonstrate an affinity to the red components of menstruation. any other way The chemical compound can be applied / treated in one or more of the described layers of the absorbent article for female hygiene. It was found that when menstruation insults the treated material, the red component of menstruation, composed of the protein hemoglobin, becomes insoluble in an aggregated form, and is retained by the article's layer, while only a clear or slightly colored solution which is relatively harmless to stain, it leaks from the insulting area. Therefore, any lateral leakage of a pad, or rewet (that is, the fluid flowing back out of the pad from the top canvas surface), demonstrates a clear or reduced-colouration appearance.

The chemical compound for menstrual fluid filtration is exemplified by polyethylene glycols (PEG) of relatively high molecular weight, polyethylene oxides (PEO), and methoxypolyethylene glycols (MPEG), with the PEGs as preferred. It was found that a wide variety of average high molecular weight PEG, PEO and MPEG, and levels of supplements can be used with the invention. In particular, it has been observed that higher molecular weight PEGs have a greater hemoglobin precipitation effect, ie, the concentration of PEG needed to induce precipitation of hemoglobin decreases as higher molecular weight PEGs are used. However, since the solubility of PEG also decreases with higher molecular weights, this results in a slower filtering effect. Therefore, in one embodiment it was found that with this invention it is desirable to use polyethylene glycols or PEG and polyethylene or PEO oxides having average molecular weights of between about 300 and 2,000,000, alternatively, between about 500 and 2,000,000, alternatively between about 1,000 and 1,000,000, alternatively between about 1,000 and 400,000, alternatively, between about 1,000 and 100,000, alternatively between about 3,000 and 100,000. In another embodiment, PEG or PEO having average molecular weights between about 3000 and 35,000 are desirable. As the ethylene oxide chain has an impact on the functionality of the invention, PEG variants with different functional groups at each end will also be acceptable for use in the invention. The linear as well as branched shapes will be equally acceptable for use in the invention. For example, methoxypolyethylene glycol or MPEG glycos of higher molecular weight similarly have an effect such that it is MPEGs with a molecular weight greater than or equal to about 750. These intervals demonstrated a remarkable discoloration of the menstruation of the surrounding fluid. Still in a further embodiment, PEGs having average molecular weights of between about 4000 and 12000 are desirable. Finally, other chemical derivatives, such as Cetiol-HE will have effects similar to PEG and therefore are contemplated to be within the scope of the invention.

The relative percentages of supplements, and the level of complement in grams per square meter (grams per square meter) or in percentage by weight (% by weight) of the Composition with respect to a base substrate dimension (area or weight) can vary to achieve the desired level of discoloration. The "percentage of complement level with respect to weight" is determined by subtracting the weight of the untreated substrate from the weight of the treated substrate (after any of the optional drying steps), dividing this weight calculated by the weight of the untreated substrate. , and then multiply by 100% by weight to produce one percent by weight (p). In some embodiments involving a chemical compound decolorizing agent of PEG, PEO and MPEG, the level of complement of the bleaching agents is at least about 15% by weight, alternatively, at least about 25% by weight, in some embodiments of about 15% by weight. to 190% by weight, and still in another alternative of approximately 50% by weight to approximately 200% by weight.

The level of complement in grams per square meter of the composition is the actual dry weight added (in grams) to the same area of the initial substrate. Desirably, the substrate complement levels may be in the range of about 5 to 150 grams per square meter. In an alternative embodiment, such levels of complement may be in the range of about 5 to 100 grams per square meter, and still in other embodiments of about 4 to 40 grams per meter square, or still more than about 60 to 100 grams per square meter. In particular, for a PEG with molecular weight of 8000, treatment with a level of complement at about 5 to 40 grams per square meter or alternatively between about 50-100 grams per square meter is desirable.

Since the higher molecular weight polyethylene glycols (PEGs) are solid, they can be melted and applied to nonwoven substrates by wide groove die coating ("slot coating process") or spray applications. Alternatively, the PEG can be placed in solvents such as water or alcohol and applied by saturation, atomization, contact roller, dip or various printing methods.

Such applications to nonwoven materials may be uniform or non-uniform. Since higher levels of complement of such chemical compounds have a greater bleaching effect, but also have an impact on absorbency, it is further desirable to place such bleaching agents in predominantly non-absorbent layers, or on the periphery of both the absorbent article and the absorbent article. absorbent layers. Such PEG and PEO materials are available from Dow Chemical Company under the tradenames CARBOWAX and CARBOWAX SENTRY, from Sigma Aldrich, and Acros Organics.

The additional chemical filtration compound of the Menstruation that can be used in conjunction with the structural invention includes surface active agents ("surfactants") such as those based on polyether siloxane chemical compounds. Examples of polyether siloxanes, also known as dimethicone copolyols, include but are not limited to ASIL SF 19, available from Emerald Performance Materials, LLC, Cheyenne, Wyoming, and Fluid 193C from Dow Corning ("DC193C") and Super Wetting Agent Q2- 5211 from Dow Corning ("Q2-5211"), both available from Dow Corning, Midland, MI. Other surfactants that can be used include ethoxylated fatty esters such as hydrogenated ethoxylated castor oil. Another family of surfactants that can be used includes those in the alkyl polyglycoside ("APG") category such as those described in U.S. Patent No. 6,060,636 which is incorporated herein by reference in its entirety. Examples of such surfactants include Glucopon 220 UP and Standapol 215 UP, available from Cognis Corp. of Cincinnati, OH. Another example of a surfactant that can be used as a decolorizing agent includes, Cirrasol PP 862 (formerly known as Ahcovel Base-N 62) from Croda, Inc.

As with PEGs, PEOs, and derivatives thereof, such as PEG (or MPEG) with a methyl cap on one end, it was found that a wide variety of surfactants and complement levels of an agent can be used. humectant together with the invention, as described above.

It was further found that more dense or variable density fibrous layer substrates can further improve the filtering effects of the materials of the chemical filtering agents. In particular, it was found that the substrate and chemical compounds can be manipulated to create a synergistic filtering effect. It is observed that two factors of the base substrate contribute to the filtering effect, the first is the pore size of the substrate, and the second is the capacity of absorption by capillarity of the substrate. Therefore, numerous substrates may be desirable embodiments for use as a layer containing decolorizing agent. A hydrofilically treated meltblown microfiber substrate is desirable, based on pore size and capillary absorption capabilities. Additionally, multiple layers of nonwoven materials treated with PEG, such as air laid materials, may be joined together in a stepped format to further improve the filtering effect. By step, it is understood that one piece of material joins another with some overlap, but also with some space between the layers. The stepless nonwoven fabric increases the flow path of menstruation in the same way as a highly porous / high absorption substrate by capillarity, as well increases the filtration efficiency of PEG. Such a combination can improve the barrier function of the substrate for the stain, thus limiting the visual spreading of the stain to a certain region, which allows only a clear or nearly clear fluid to pass out from the denser substrate area. . In further alternative embodiments of the article, numerous layers containing the decolorizing agent may be separated by interruptions or physical spaces, or one or more layers within the article, or alternatively, placed one on top of the other (immediately adjacent to one another in the depth direction). ) from the article. Such a separation would aid in the distribution / absorption by lateral and longitudinal capillary action of the menstrual fluid stain in the article.

In order to test the PEG chemical compounds for their intended use, the following experiments were carried out: Experimental examples General procedure for producing substrates treated with PEG of high average molecular weight, and related chemical compounds PEG with molecular weight sizes of different averages were applied to non-woven materials by immersing the non-woven samples and subsequently air-dried, with 5, 10, 15, 20, 25, 30% (w / w) of solution of PEG in water on a single-layer air-laid substrate, based on latex-bound pulp, of 60 grams per square meter (Sambo, Korea). The complement was 0.37 to 0.40 grams of PEG. The PEGs were obtained from Dow Chemicals, in granular or flake form under the tradename CARBOWAX, from Sigma Aldrich, and from Acros Organics. First the PEG was dissolved in distilled water at a concentration of 20%. The air laying was immersed in the PEG solution, the excess liquid was removed by suspending it in the air for 15 minutes and then drying in an oven at 80 C in a flat state for 2 hours. Alternatively, the sample was allowed to air dry for two days. The canvases obtained and treated were tested to observe the discoloration by filtration on the canvases. For the purposes of these experiments, the filtration of the canvases was carried out by dropping 0.1-0.3 grams of menstrual fluid simulator, or alternatively 200 uL, drop by drop from a pipette on the canvases. The canvases were then examined to see if there was a space or area of discoloration in the stain as it was absorbed by capillarity into the substrate that resulted from separating the plasma (a clear fluid) from the red blood cells or the hemoglobin. For the purposes of these experiments, the complement was calculated as the percentage of the added weight of PEG divided by the basis weight of the base material.

Canvases treated with PEG of average molecular weight of 3015-3685 (Sigma Aldrich) showed a partial discolored space (1 mm) from the colored regions of menstrual fluid, from a complement level of 90% to 190% (approximately 2 mm). A higher level of PEG complement gave a wider discoloration space (l ~ 2mm), but no more than 2 mm space, and became stiffer on the canvas, as a higher level of complement was used.

The canvas treated with PEG of average molecular weight of 7000-9000 (Acros Organic) showed a partial discolored space (less than 1 mm) from the regions colored with menstrual fluid, from a complement level of 60% to 190 %. A higher level of PEG complement showed a wider discoloration space (1-2 mm), but no more than 2 mm space, and became stiffer on the canvas, using a higher level of complement.

A canvas treated with PEG of average molecular weight of 16000-24000 (Sigma Aldrich) showed a partial discolored space of the regions colored with menstrual fluid, from a complement level of 60% to 190%. A higher level of PEG complement showed a wider discoloration space (1-2 mm), but no more than 2 mm space, and the canvas became stiffer, using a higher level of complement.

A canvas treated with PEG of average molecular weight of 35,000 (Sigma Aldrich) showed a partial discolored space of the regions colored with menstrual fluid, from a complement level of 60% up to 190%. A higher level of complement showed a wider discoloration space (1-2 mm), but no more than 2 mm space, and became stiffer on the canvas, using a higher level of complement.

In the tests with PEG of different molecular weights, for the PEG of higher molecular weight a smaller amount of complement was required for the same discoloration of the menstrual fluid simulator, but it was observed that for the PEG with a molecular weight above 8000, the differences were not significant in the observation of filtration. It was further observed that the solubility of PEG in aqueous medium was significantly reduced with the increase in molecular weight. As more time was needed for the PEG to solubilize, the discoloration space was reduced.

The fabrics of melt blown microfibers (BF polypropylene) were also used in the experiments, with a basis weight of 50 grams per square meter. It should be noted, however, that MBMF frames of 20 and 60 grams per square meter are also available. The canvases were supplied by Yuhan-Kimberly Ltd. Korea, and they are also available from FiberTex, Malaysia. The canvases were hydrophilically treated by Cytec Aerosol GPG, or alternatively Ahcovel Base N-62.

In particular, a MBMF canvas of 50 grams per square meter treated hydrophilically was treated with PEG of average molecular weight of 3015-3685 and PEG of average molecular weight of 7000-9000 by immersion and air drying with PEG solution in water at room temperature. 30% (p / p), which gave 130% or 106% of complement amount in the MBMF respectively. These canvases were analyzed for the discoloration of the menstrual fluid simulator by filtration in the canvases. A superior resulting discoloration space (3-5 mm) was demonstrated. Additionally, the resulting meltblown material appeared to be softer than pulp-based airlaying.

MPEG was also tested for its ability to bleach menstrual fluid. In particular, the same general test procedures were employed. The MPEG was obtained from Dow Chemical with an average molecular weight of about 750. A mPEG solution of 15% by weight was prepared. The air-laid or MBMF substrates were immersed in the solution and air-dried. A few drops of simulator (1-3 drops) were placed on the substrate treated with mPEG and after a couple of minutes, a clear fluid was observed as along the peripheral areas around the simulator on the substrate.

In a further embodiment, it was found that the carbomer and the salt-containing chemical successfully separate the coloring agents from the menstrual fluid from the non-colored portions of the menstrual fluid. In particular, the decolorizing agent for a layer containing decolorizing agent is selected from the group of trichloroacetic acid, ammonium sulfate and acrylate polymers (carbomers) or combinations thereof, with the optional addition of salts other than ammonium sulfate. It was found that such materials are particularly desirable treatments to be placed specifically on or adjacent to an absorbent core layer, or alternatively, on a carrier layer that will be placed between an absorbent core layer and a bottom canvas layer. Such a carrier layer may be selected from foams, sponge-like nets, non-woven fabrics such as tissue layers, fabrics or particles, and desirably would extend beyond the side edges of the absorbent layer (s) of the absorbent layer (s). core, as shown in Figure 2B. For non-woven carrier layers, such as tissue, in one embodiment it is desirable that such base weights be between about 50 and 150 grams per square meter. For carrier layers similar to foam, in one embodiment it is desirable that such base weights are between approximately 100 and 200 grams per square meter.

An effective combination for use in an absorbent core layer or carrier layer is a mixture of an acrylate polymer and a salt. Examples of the acrylate polymer that is desirable include carbomer available through Lubrizol, Ohio and Spectrum Chemicals of New Jersey and California. In addition, carbomers from other manufacturers and suppliers can be used. Specific examples of desirable carbomers include Carbopol ETD 2020, Carbopol Ultrez 21, Carbopol 980 NF, and Carbopol 1342 NF from Lubrizol. Examples of salts that are used with such an acrylate polymer include sodium chloride, magnesium chloride, potassium chloride and ammonium sulfate.

For this chemical combination, a suspension of the carbomer and a salt solution can be prepared by mixing in water and stirring until a suspension is achieved. The suggested dispersion techniques are described in more detail on the Lubrizol corporate websites. In one embodiment, an acceptable range of such combination would be between about 0.1% to 1% carbomer and between about 4 and 20% salt. Desirably this can be applied to a fibrous material or open cell foam (or foam-like material) and dried. A substrate is loaded with this combination as described and then, if it is loaded onto a carrier layer, it is placed adjacent to the carrier layer. absorbent core of an absorbent article (such as between the core layer and the bottom canvas layer). In this way, any slowly absorbed menstrual fluid comes into contact with the bleaching agent and undergoes discoloration, without affecting the absorbance level of a core layer. Over a period of time, the bleached menstrual fluid separates onto the treated substrate. The red color is limited to the center of the pad, if it is applied to a core layer located centrally or to the carrier layer, and a relatively colorless liquid is allowed to pass beyond the core, when leaks actually occur. Desirably in one embodiment, the chemical compound is applied to a substrate by the use of a submerging and squeezing or atomizing method and at complement levels / carbomer amounts between about 9 and 33 grams per square meter, NaCl between about 17-78 grams per square meter, and ammonium sulfate of between approximately 16-310 grams per square meter. In a desirable embodiment, an absorbent core layer is treated by an immersion or atomization method with between about 50 and 300 grams per square meter of ammonium sulfate and a foam carrier layer is treated by an immersion or spray method with approximately 20 grams per square meter of NaCl and between approximately 11-16 grams per square meter of carbomer. Such a carrier layer it can have a dimension similar to a BFDL contained in the article and extends beyond the peripheral dimensions of the absorbent core layer at least along the longitudinal side edges (side sides) of the core layer.

Experimental examples of carbomer: In several experiments, a nonwoven material such as tissue or meltblown material, or foam was immersed in a suspension consisting of 0.7% Carbopol ETD 2020 and 8% NaCl and allowed to stir on an orbital shaker for about 10 hours. minutes The material was removed with a clamp and the excess fluid was removed by holding it gently on a sink. Then the material was transferred to a polypropylene mesh to dry it. Alternatively, for thin non-woven samples, first the material was laid flat on the polypropylene mesh and then sprayed with the treatment solution through a spray bottle. As with the previous method, excess fluid was allowed to spill into a sink area. Regardless of the treatment methods, the treated materials were allowed to dry in an oven at, between about 50-60 ° C. For foam materials, the drying temperature was kept below 60 ° C.

Once completely dry, the materials were removed and used for testing. The treated materials were laid under an absorbent core layer, with a non-woven inlet layer located at the top of the absorbent core layer. The dimensions of the treated materials extended beyond the absorbent core layer, so that they were easily visible when viewed from above, and could be seen to extend beyond the edges of the superimposed absorbent core layer. The samples were placed on a weight scale and insulted with between about 5 and 10 g of menstrual fluid simulator on top of the non-woven inlet layer by using a plastic transfer pipette and the simulator was dropped slowly in a central region until the desired weight of the insult was achieved. The menstrual fluid simulator was then allowed to absorb the core from the fluid transfer. After 1 to 2 hours or more, filtration of the coloring components of the menstrual fluid simulator was observed, so that a clear fluid was absorbed by capillarity to the side edges of the treated material (as observed at least along the the upper surface of the treated material), while the red spot occurred at the center of the core layer in the initially dirty region. It was observed that the amount of fluid absorbed by capillarity increased with increasing time and amount of insult.

Experimental examples with zinc oxide: In a further embodiment of the invention, a suspension of zinc oxide in water and surfactants was found to adsorb (and therefore filter) the red protein contained in the menstrual fluid. It was found that for such a system to be successful, it is desirable that acidifying agents be present in the layered structure to maintain the relative pH at a desired level of between about 3 and 6. Additionally, the zinc oxide must be stably attached to a layer substrate. As a result, in one embodiment of a decolorization mixture with zinc oxide, the mixture includes zinc oxide particles, a surfactant for dispersing the zinc oxide, an acidifying agent, a binder for binding the zinc oxide to a zinc oxide substrate. Nonwoven or other material and a solvent. The mixture can be applied to a substrate in one step, rather than through a multi-step process. Desirably in the suspension, the zinc oxide is present in an amount of between about 0.1% by weight and 20% by weight, more desirably in an amount between about 0.5% by weight and 10% by weight, a surfactant is present in an amount between about 0.1% by weight and 20% by weight, more desirably between about 0.5% by weight and about 10% by weight, an acidifying agent is present to create a pH range of between 3 and 6, a binder is present in an amount of between about 0.1% by weight and 10% by weight, more desirably between about 0.5% by weight to 5% by weight. Examples of such ZnO particles include Solaveil CZ-300 from Croda (Edison, NJ), zinc oxide from NanoScale Materials, Inc., Manhattan, KS. Examples of such surfactants include DC 193 C from Dow Corning (Midland, MI) and Ahcovel Base N-62 from ICI. In one embodiment, super wetting agents are more desirable, such as a siloxane polyether. Examples of such acidifying agents include lactic acid from Sigma Aldrich (Milwaukee, WI). Examples of such binders include chitosan such as Hydagen HCMF from Cognis (Cincinnati, OH). Desirably, the blend has a complement of between about 0.2 and 20% by weight of a variety of substrate materials, including microfiber blown melt materials and other nonwovens and laminates having similar capillary structures. Such a mixture of zinc oxide may also include other functional chemical compounds as desired, such as, for example, preservatives, antioxidants, flavors, pigments and anti-microbial agents. Additionally, instead of zinc oxide, other metal oxides such as silica can be used, also in lower pH environments. The application is desirably applied to a substrate by the use of atomization, saturation, slot die, foam and printing methodologies.

Zinc oxide formulations: The samples were prepared from non-woven fabrics of melt blown microfibers at 35 grams per square meter. The melt-blown layer was treated through the saturation method (dip and squeeze methods) by the use of a laboratory drainer and the samples were allowed to dry at typically 80 ° C for 1 hour or until a weight was reached constant. The material was treated at a complement level of about 10 weight percent. The menstrual fluid was contacted with such samples by depositing a 2 ml droplet of the menstrual fluid simulator.

Formulation 1 Formulation 2 Formulation Formulation 4 For each of the above formulations, the menstrual fluid simulator was successfully filtered, since it was visually observed that the red dye was isolated from the scattering of surrounding fluid. However, for formulation 3, good absorption properties were observed by capillarity but the discoloration was not as pronounced as in other examples where ZnO was present. In one embodiment it is desirable to include the ZnO mixture as a treatment in the side materials of the two-layer top canvas or in the materials of the edge-core side wrapping.

Each of such filter chemical compounds described above can be used in a further embodiment, with a polymer barrier line applied to one or more layers. Such a polymer barrier can be placed on a substrate, such as, for example, the peripheral portions of the absorbent layer or side edge and the core envelope substrates previously described in Figures 1C-1E, 1H, 1J and 1K. Essentially, the polymer barrier can be applied in a discontinuous or desirably continuous line or strip to a layer of the article, which thus creates a physical barrier material to block the flow of the menstrual fluid. Such a polymer barrier may include a co-polymer system containing a mixture of hydrophilic and hydrophobic monomers which are water soluble, but which act as a barrier when applied to a substrate. Examples of such polymers include acrylic acid, 2-acrylamido-2-methylpropane sulfonic acid and sodium salt, n-butyl acrylate and 2-ethylhexyl acrylate. Such a mixture may include surfactants or amphiphilic molecules such as sodium lauryl sulfate and sodium lauryl sulfosuccinate. Water-insoluble polymers may include, for example, acrylates (C12-22), alkyl methacrylate copolymer, and acrylate / octylacrylamide copolymer. It was found that the application of such materials still allows a level of softness in a substrate. The polymer barrier can be applied in one embodiment by printing or atomizing a solution of 5 to 20% (w / w) in alcohol at a complement level of between about 0.1% and 20%. Desirably, the polymer is applied at 1% up to 10%, and between approximately 0.5 and 10 mm at the most lateral edges from the article.

A variety of techniques can be used to apply the bleaching agent compositions to either a predominantly nonabsorbent carrier substrate. For example, the composition of the decolorizing agent can be applied by the use of rotogravure or gravure printing, either direct or indirect (separate). Engraving printing encompasses several well-known etching techniques, such as mechanical etching, acid etching, electronic engraving and laser engraving in ceramics. Such printing techniques provide excellent control of the composition distribution of the agent and the transfer rate. Engraving printing can provide, for example, from about 10 to about 1000 deposits per linear inch of the surface (about 4 to about 393 deposits per linear cm), or from about 100 to about 1,000,000 deposits per square inch (from about 15 to 15504 deposits per cm2). Each deposit results from an individual cell on a printing roller, so that the density of the deposits corresponds to the density of the cells. An example of electronic etching suitable for a primary delivery zone is approximately 200 deposits per linear inch of surface (approximately 78 deposits per linear cm), or approximately 40,000 deposits per square inch (approx. 6201 deposits per cm2). By providing such a large number of small deposits, the uniformity of the deposit distribution can be improved. In addition, due to the large number of small deposits applied to the surface of the substrate, the deposits resolidify more easily in the exposed portions of fiber. Suitable etching techniques are described further in U.S. Pat. 6,231,719 to Garvey, et al., Which is incorporated herein by reference in its entirety for all purposes. On the other hand, in addition to printing by engraving, it should be understood that other printing techniques, such as flexographic printing, can also be used to apply the composition.

Still another suitable contact printing technique that can be used in the present invention is "screen printing." Silkscreening is done manually or photomechanically. The screens may include a mesh of silk or nylon fabric with, for example, from about 40 to about 120 openings per linear centimeter. The screen material is attached to a frame and stretched to provide a smooth surface. The template is applied to the side of the lower part of the screen, that is, the side in contact with the substrate on which the composition is to be printed. The decolouring composition is painted on the screen, and transferred by rubbing the screen (which is in contact with the substrate) with a rubber roller.

Inkjet printing techniques can also be employed in the present invention. Inkjet printing is a non-contact printing technique that involves forcing an ink through a small nozzle (or a series of nozzles) to form goths that are directed towards the substrate. Two techniques are generally used, ie printing "DOD" (Drop on Demand) or CIJ (continuous ink jet). In ICJ systems, ink is emitted in a continuous stream under pressure through at least one orifice or nozzle. The current is disturbed by a pressurizing actuator to decompose the current into Gothic at a fixed distance from the orifice. DOD systems, on the other hand, use a pressurization actuator in each hole to break the ink into gothic. The pressurization actuator in each system can be a piezoelectric crystal, an acoustic device, a thermal device, etc. The selection of the type of ink jet printing system varies depending on the type of formulation used and the material to be printed from the print head. For example, low viscosity formulations are sometimes required (eg = 2 cps) for CIJ printing systems while higher viscosity formulations = 2 cps) can be used with a DOP printing system.

In addition to the printing techniques mentioned above, any other suitable application technique can be used in the present invention. For example, other suitable printing techniques may include, but are not limited to, laser printing, thermal tape printing, piston printing, spray printing, flexographic printing, etc. Still other suitable application techniques may include bar, roller, knife, curtain, atomizer, slot die, dip coating, drop coating, extrusion, template application, etc. Such techniques are well known to those skilled in the art.

Regardless of the method of application, sometimes the substrate can be dried at a certain temperature to control any solvent in the bleaching composition. For example, the treated substrate may be heated to a temperature of at least about 80 ° C, in some embodiments at least about 120 ° C, and in some embodiments, at least about 150 ° C. Generally the required drying temperature is dependent on the level of solvent (e.g., water) present in the substrate after treatment and the line speed during a typical continuous production process. In other words, a temperature is applied during a residence time that is necessary to evaporate the solvent. By minimizing the amount of solvent in the bleaching agent composition, a greater amount of the agent may be available to be placed in contact with body exudates, which improves its ability to discolor hemoglobin or other colored substances contained in menstrual exudates.

It was found that the leakage of the female pads frequently results from residual insults of menstrual fluid in the pad at or near the upper canvas layer, surface of a pad facing the wearer. Such residual insult is not contained by the absorbent layer (s) as a result of fluid saturation of the layer or by impeding the flow of an insult to the absorbent structure. By "impediment", it is understood that the flow is slowed or restricted as a result of the structure of the absorbent layer, or alternatively, it is not absorbed quickly enough as a result of a sudden insult. Such a prevented flow can result in spillage of the pad insult, even when the absorbent layer is not saturated. With the development and popularity of pads and liners for progressively thinner and smaller feminine hygiene (surface area), the leakage potential has been amplified. Depending on the characteristics of the design, the pads may have lower overall capacity, having smaller absorbent areas. When an absorbent layer becomes saturated, the menstrual insult can accumulate on the surface of the pad that can subsequently spilling from the side edges of the pad to a garment or bedding, or transferring through contact with the body to a garment or bedding. Because spillage and buildup are often the immediate causes of staining on thinner female pads, the disclosed invention has addressed such causes by directing fluid flow not only in the absorbent layers, but also in the nonabsorbent layers at the side edges of a pad. Additionally, the disclosed invention has helped to reduce the overall size of the stain in the upper canvas layer as a result of both bleaching agents in the layers and the use of the stain masking technology together with such bleaching agents. Such a reduction in the size of the stains has led to smaller sizes of the stains in the upper canvas layer, and to relatively larger sizes of the stains located internally or in the absorbent core layer (the overall size of the stain is surface area) compared to the size of the stain on the upper canvas layer. Such reduced color (in the side areas of the pad) and the reduced size of the stain, can help provide comfort, and instill confidence in some consumers who use such absorbent products. Finally, by separating the components that produce the color of the menstrual fluid within the Female hygienic pad, by using a layer (or layers) containing a decolorizing agent, strategically placed and constructed, the components of lower viscosity of menstruation can be absorbed more effectively by the layer structures of the absorbent core.

Although the invention has been described in detail with respect to the specific modalities thereof, it will be appreciated that those with experience in the art, after reaching an understanding of the foregoing, can easily conceive alterations, variations, and equivalents to these modalities. Accordingly, the scope of the present invention should be evaluated as that of the appended claims and any equivalent thereto.

It is noted that in relation to this date, the best method known to the applicant to carry out the aforementioned invention, is that which is clear from the present description of the invention.

Claims

CLAIMS Having described the invention as above, the content of the following claims is claimed as property:

1. A personal care absorbent article for feminine hygiene characterized in that it comprises an upper canvas layer, a lower canvas layer, and at least one absorbent core layer located between the upper canvas layer and the lower canvas layer, the article of personal care for female hygiene has a longitudinal axis and longitudinally directed lateral edges, a transverse axis, and a depth axis and the absorbent core layer includes lateral edges, directed longitudinally, wherein a decolorizing agent is located in at least one layer containing bleaching agent within the personal care article for feminine hygiene, adjacent to the longitudinally directed side edges of the article, that at least one layer containing bleaching agent extends laterally beyond the longitudinally directed side edges of the layer of absorbent core, and even more so where the at least one layer containing The bleaching agent includes a portion that is not continuous through the transverse axis of the personal care absorbent article for feminine hygiene.

2. The personal care absorbent article for feminine hygiene of claim 1, characterized in that it has two separate layers containing decolorizing agent.

3. The personal care absorbent article for feminine hygiene of claim 1, characterized in that the bleaching agents are located in the upper canvas layer.

4. The personal care absorbent article for feminine hygiene of claim 3, characterized in that the upper canvas layer includes a central material of longitudinal upper cloth directed longitudinally and two upper canvas materials of longitudinally directed lateral edges, and even more so where a decolorizing agent is located in the two upper canvas materials of the lateral edges directed longitudinally.

5. The personal care absorbent article for feminine hygiene of claim 4, characterized in that the two materials of the longitudinally directed side edges are composed of a laminate that includes a masking layer.

6. The personal care absorbent article for feminine hygiene of claim 5, characterized in that the laminate includes a non-woven layer and a film layer.

7. The absorbent article of personal care for the The feminine hygiene of claim 2, characterized in that the absorbent core layer includes core-edge side wraps, and even more so where a bleaching agent is located in the core-edge side wraps.

8. The personal care absorbent article for feminine hygiene of claim 2, characterized in that the absorbent core layer includes a main absorbent layer and side edge materials bonded to the main absorbent layer including a decolorizing agent.

9. The personal care absorbent article for feminine hygiene of claim 8, characterized in that the materials of the side edges are a laminate that includes a masking element.

10. The personal care absorbent article for feminine hygiene of claim 9, characterized in that the laminates are attached to the absorbent core layer at a location facing the lower linen layer.

11. The personal care absorbent article for feminine hygiene of claim 8, characterized in that the absorbent core layer is at least partially enveloped by a secondary absorbent layer.

12. The personal care absorbent article for feminine hygiene of claim 1, characterized in that it further includes a carrier layer with a decolorizing agent located between the absorbent core layer and the absorbent layer. lower canvas.

13. The personal care absorbent article for feminine hygiene of claim 1, characterized in that the bleaching agents are selected from PEG, PEO or MPEG.

14. The personal care absorbent article for feminine hygiene of claim 1, characterized in that the bleaching agents are selected from ammonium sulfate and carbomer.

15. The personal care absorbent article for feminine hygiene of claim 1, characterized in that the bleaching agents include a mixture of zinc oxide.

16. The personal care absorbent article for feminine hygiene of claim 2, characterized in that the bleaching agents include two different chemical compounds, each chemical compound being present in a different layer.

17. The personal care absorbent article for feminine hygiene of claim 12, characterized in that the carrier layer is treated with a carbomer and a salt.

18. The personal care absorbent article for feminine hygiene of claim 16, characterized in that the absorbent core layer includes ammonium sulfate.

19. The absorbent article of personal care for the Female hygiene of claim 15, characterized in that the zinc oxide mixture is composed of zinc oxide, a binder, at least one surfactant, and an acidifying agent.

20. The personal care absorbent article for feminine hygiene of claim 13, characterized in that the decolorizing agent is a PEG having an average molecular weight in the range of between about 1000 and 400,000.

21. A personal care absorbent article for feminine hygiene characterized in that it comprises an upper canvas layer, a lower canvas layer, and at least one absorbent core layer located between the upper canvas layer and the lower canvas layer, the absorbent article of personal care for feminine hygiene has a longitudinal axis and longitudinally directed lateral edges, a transverse axis and a depth axis and the absorbent core layer includes lateral edges, directed longitudinally, wherein a decolorizing agent is located in at least one layer containing bleaching agent within the personal care absorbent article for feminine hygiene, adjacent to the lateral edges of the article, directed longitudinally, in which at least one layer containing decolorizing agent extends laterally beyond the lateral edges, directed longitudinally, of the absorbent core layer, and wherein the at least one layer containing decolorizing agent includes a portion that is not continuous through the transverse axis of the personal care absorbent article for feminine hygiene, and even more so where the at least one layer containing bleaching agent includes a laminate of a non-woven meltblown layer and a film layer.